Second Avenue Subway Discussion

[LTA1992]

2 hours ago, LGA Link N train said:

Well. If the terminal for the Second Avenue subway was 3 Avenue-149 Street, then you have access to the and , but that's not the point. What the case here would be is that if the decided to do this, then we'd be a step close to bringing back subway service to 3 Avenue, as opposed to 125 Street which I don't advocate for, despite seeing it's importance for a possible extension.

And you would be able to give The Bronx two lines instead of one. I don't feel like reiterating 10-walls worth if text on why that's a better terminal than 125th and Lex today. 

People may say that the river tube will drive up costs, but compared to spending around 3 Billion on a single terminal, it's worth it. Plus, the Harlem River isn't that long nor that deep. With the Immersed Tunnel method, that thing should t even cross the 1 billion mark in price. 

[Wallyhorse]

3 hours ago, LTA1992 said:

And you would be able to give The Bronx two lines instead of one. I don't feel like reiterating 10-walls worth if text on why that's a better terminal than 125th and Lex today. 

People may say that the river tube will drive up costs, but compared to spending around 3 Billion on a single terminal, it's worth it. Plus, the Harlem River isn't that long nor that deep. With the Immersed Tunnel method, that thing should t even cross the 1 billion mark in price. 

I would definitely have that as an option with the line eventually extended to Gun Hill Road in a full rebuild of the former 3rd Avenue EL Bronx route (as subway), however, 125th is also important as I would have it go all the way across 125th Street to Broadway with transfers to ALL of the lines across 125 AND a connection to the 8th Avenue Line at St. Nicholas Avenue that would allow for a possible SAS via Councourse or SAS to 207 as well.  

[Porter]

I say we make it a forum community tradition to propose sending the SAS to 138th and 149th streets along 3rd Avenue. I'd happily participate, on behalf of those deserving riders.

 

 

...and the riders in all but name...?

Edited February 2, 2018 by Porter

[RailRunRob]

On 1/26/2018 at 3:29 PM, LTA1992 said:

And you would be able to give The Bronx two lines instead of one. I don't feel like reiterating 10-walls worth if text on why that's a better terminal than 125th and Lex today. 

People may say that the river tube will drive up costs, but compared to spending around 3 Billion on a single terminal, it's worth it. Plus, the Harlem River isn't that long nor that deep. With the Immersed Tunnel method, that thing should t even cross the 1 billion mark in price. 

Not deep at all 20 feet deep 600-800 feet of Tube or sunken tunnel.  

[Wallyhorse]

This is especially the case if you can somehow make it so eventually. such an SAS extension to The Bronx were to go to Gun Hill Road to be a full replacement for the long-demolished 3rd Avenue EL there (either as subway or elevated).  

[LGA Link N Train]

9 hours ago, Wallyhorse said:

This is especially the case if you can somehow make it so eventually. such an SAS extension to The Bronx were to go to Gun Hill Road to be a full replacement for the long-demolished 3rd Avenue EL there (either as subway or elevated).  

Subway would be a better idea, but to have it go to Gun Hill Road. ...... I don't know man. 

[RailRunRob]

19 minutes ago, LGA Link N train said:

Subway would be a better idea, but to have it go to Gun Hill Road. ...... I don't know man. 

What don't you know?

 

[LGA Link N Train]

1 hour ago, RailRunRob said:

What don't you know?

 

If a third Avenue subway ended at gun hill road

[Caelestor]

On the topic of Third Avenue, I see marginal benefit extending the subway past Fordham Plaza. Ridership potential is low, seeing as the Bx55 was just cut recently. A double solution of extending the  to Gun Hill Road  and extending the SAS along Fordham Road / Pelham Parkway is my preferrence. 

[T to Dyre Avenue]

On 1/26/2018 at 3:29 PM, LTA1992 said:

And you would be able to give The Bronx two lines instead of one. I don't feel like reiterating 10-walls worth if text on why that's a better terminal than 125th and Lex today. 

People may say that the river tube will drive up costs, but compared to spending around 3 Billion on a single terminal, it's worth it. Plus, the Harlem River isn't that long nor that deep. With the Immersed Tunnel method, that thing should t even cross the 1 billion mark in price. 

It really shouldn’t, even with New York’s absurdly inflated construction costs. I mean, we’re taking about a single prefabricated structure with only two tubes. It’s on a much smaller scale than the 63rd St Tunnel was. That was four tubes in two structures under both channels of the East River. For $3 billion, I’d much prefer to get a least a foothold in the Bronx with one station at 138th St-3rd Ave and be able to siphon riders off of already overcrowded  trains who currently  bum rush the  and  trains at 125th... most of whom I suspect would continue to do so if Phase 2 is built as currently planned. That’s because the  platform is planned to be located so far below the Lexington platforms. You can locate a  platform just below the  platforms at 138th and 3rd, because the  platforms are on a single level, so the  platform wouldn’t have to be built so far below them.

And please, nobody mention how elevators and escalators will make transfers between the  and the  at 125th and Lex easy, because we all know what the MTA’s track record on elevator/escalator maintenance is.

21 hours ago, RailRunRob said:

Not deep at all 20 feet deep 600-800 feet of Tube or sunken tunnel.  

 

Right, the 63rd St Tunnel is much deeper than that. And it technically crosses the East River twice, whereas this would be just one uninterrupted crossing under the Harlem River. Then locate a 125th and 2nd station roughly from 124th to 121st streets to better serve all the high-rises on 2nd and 3rd in between those streets. 

2 hours ago, Caelestor said:

On the topic of Third Avenue, I see marginal benefit extending the subway past Fordham Plaza. Ridership potential is low, seeing as the Bx55 was just cut recently. A double solution of extending the  to Gun Hill Road  and extending the SAS along Fordham Road / Pelham Parkway is my preferrence. 

This does make more sense than extending the SAS past Fordham, up Webster Ave for a connection with the , then having both inter-line across Gun Hill Road, which seems to be a quite frequent idea for how to extend both lines in the Bronx. By having the  connect to the  at Gun Hill Road and the SAS connect at Pelham Pkwy, both lines can run more frequently. They would be forced to run less frequently if they reverse-branched off Gun Hill Road. 

Edited February 2, 2018 by T to Dyre Avenue

[RailRunRob]

3 hours ago, Caelestor said:

On the topic of Third Avenue, I see marginal benefit extending the subway past Fordham Plaza. Ridership potential is low, seeing as the Bx55 was just cut recently. A double solution of extending the  to Gun Hill Road  and extending the SAS along Fordham Road / Pelham Parkway is my preferrence. 

Have people's travel patterns changed?  The Original 3rd Ave thru express took a pretty direct path to Manhattan, in fact, it prob was a faster run from 241or Gunhill to South Ferry or on par with the Lex in peak direction. Are we sure the ridership isn't there?  

[bobtehpanda]

1 hour ago, RailRunRob said:

Have people's travel patterns changed?  The Original 3rd Ave thru express took a pretty direct path to Manhattan, in fact, it prob was a faster run from 241or Gunhill to South Ferry or on par with the Lex in peak direction. Are we sure the ridership isn't there?  

The original 3rd Av was also built through farmland. Given that stops are nearly a billion a pop, we have to start cutting losses somewhere.

Also, it wouldn't make sense to build this Central Bronx line with three tracks. Doubtful it'd be much faster with two. The  gets from Gun Hill to Intervale in 19 minutes, while the gets from Norwood-205 to Yankee Stadium in 20. Given that the  from Gun Hill to 3 Av-149 is scheduled for 25 minutes, there's no way it'd be any sort of sizeable time savings.

 

[RailRunRob]

38 minutes ago, bobtehpanda said:

The original 3rd Av was also built through farmland. Given that stops are nearly a billion a pop, we have to start cutting losses somewhere.

So did every other line into the Northern Bronx besides the IND. I'm not sure of your point there. They ran a THRU Express for a reason. I'm speaking on ridership demand not cost.  Heck if they actually get it that far north whats another 6-7,000 feet?

38 minutes ago, bobtehpanda said:

Also, it wouldn't make sense to build this Central Bronx line with three tracks. Doubtful it'd be much faster with two. The  gets from Gun Hill to Intervale in 19 minutes, while the gets from Norwood-205 to Yankee Stadium in 20. Given that the  from Gun Hill to 3 Av-149 is scheduled for 25 minutes, there's no way it'd be any sort of sizeable time savings.

 

3

The original 3rd did Gun Hill to 149th in 20 mins with the Express coming in at about 17 mins. Back to my point of it being a more direct path. The   and  are for the most part straight and narrow path kinda hard to compare to  that weaves through the borough. 

[bobtehpanda]

3 hours ago, RailRunRob said:

So did every other line into the Northern Bronx besides the IND. I'm not sure of your point there. They ran a THRU Express for a reason. I'm speaking on ridership demand not cost.  Heck if they actually get it that far north whats another 6-7,000 feet?

The original 3rd did Gun Hill to 149th in 20 mins with the Express coming in at about 17 mins. Back to my point of it being a more direct path. The   and  are for the most part straight and narrow path kinda hard to compare to  that weaves through the borough. 

That's my point. The  isn't all that much slower than the traveling more distance. There's not a lot of marginal speed benefit Gun Hill riders get if you bring the SAS all the way there.

[RailRunRob]

7 hours ago, bobtehpanda said:

That's my point. The  isn't all that much slower than the traveling more distance. There's not a lot of marginal speed benefit Gun Hill riders get if you bring the SAS all the way there.

I understand that to a degree I'm sure a new 3rd ave line would skip a few stops the old route took. Including a more direct route to GunHill Station under Bronx Park. Skipping the old Williamsbridge station. You have the Concourse line tunnel already at Webster tie that in even if just for Yard Access. I guess my second question is how are you measuring marginal? I'm sure this could save 10 mins in the Bronx alone one way.  An hour 40 mins savings for someone between those two points a week is a solid measurement for some other projects. Note I stated 241to South Ferry or Gun Hill to South Ferry with the original 3rd ave line. This would give riders in Wakefield, Williamsbridge,  Norwood, Bedford Park and Fordham another major route to the Eastside of Manhattan beside the .. I could see some trips cut by 20-25%. I also couldn't see 149th as being able to hold major additional ridership as a transfer point, What's there now plus with the South Bronx resurgence and development. Spread it out.  Penny wise dollar dumb ... isn't the way to plan. Do the research view the full picture and then make the call.. Disengage gut reactions I think this is something that at least requires a look.

Edited February 3, 2018 by RailRunRob

[RailRunRob]

1 hour ago, Coney Island Av said:

I see we're talking about Bronx SAS expansions. 

Well's here's how I think it should roll out. 

Phase 1

The  diverges from the  at 125 St and runs across the latter to Broadway, with connections to the . 

 continues to 3 Av-149 St, where tail tracks will be left to extend the line further to Gun Hill Rd via 3 Av. 

Grand St, Houston St, 14 St, 42 St, 55 St, 3 Av-138 St, 3 Av-149 St, and 161 St-Morrisania will be 4-track stations, with provisions for SAS express service.

Phase 2

 is extended to Gun Hill Rd, and  is extended to Co-op-City. A cross-platform transfer will be available at Gun Hill. Non revenue tracks will be made to the Concourse Yards. 

Provisions for an extension via Lafayette Av to Throgs Neck will be left at 163 St, just north of 161 St-Morrisania. 

A third track is installed, allowing peak express service on 3 Av. Express stations north of 161 St are E Tremont Av, Fordham Plaza, Bedford Park Blvd, and Gun Hill Rd. The rest, 167, 170, Claremont, 183 St, and 204 St will all be local stops. 

 

 

 

What's the bandwidth of a full SAS? TPH?  

[RR503]

28 TPH according to the FEIS. So 14 each to 125 and the BX. 

I don't think adding a 3rd track in the Bronx would be all that helpful. First off, you're halving frequencies to stops along the dense part of the corridor, and even then, you're not saving all that much time. You're only skipping 5 stops -- best case scenario that's maybe 3 or 4 minutes of time saved. Finally, if you just build local stops far enough apart, you can get near-express speeds without the extra cost of express tracks. I'd say just do that. 

[officiallyliam]

2 hours ago, Coney Island Av said:

I see we're talking about Bronx SAS expansions. 

Well's here's how I think it should roll out. 

Phase 1

The  diverges from the  at 125 St and runs across the latter to Broadway, with connections to the . 

 continues to 3 Av-149 St, where tail tracks will be left to extend the line further to Gun Hill Rd via 3 Av. 

Grand St, Houston St, 14 St, 42 St, 55 St, 3 Av-138 St, 3 Av-149 St, and 161 St-Morrisania will be 4-track stations, with provisions for SAS express service.

Phase 2

 is extended to Gun Hill Rd, and  is extended to Co-op-City. A cross-platform transfer will be available at Gun Hill. Non revenue tracks will be made to the Concourse Yards. 

Provisions for an extension via Lafayette Av to Throgs Neck will be left at 163 St, just north of 161 St-Morrisania. 

A third track is installed, allowing peak express service on 3 Av. Express stations north of 161 St are E Tremont Av, Fordham Plaza, Bedford Park Blvd, and Gun Hill Rd. The rest, 167, 170, Claremont, 183 St, and 204 St will all be local stops. 

 

 

 

I like this plan, but think the and should be the other way around. The already connects with all those other lines at Times Square and Union Square, since the Broadway Line acts as a sort-of circumferential through Midtown. The should be the one to go across 125 to allow folks from the West Side of Upper Manhattan to reach the Lower East Side easier and faster, instead of the which will just loop people back to the West Side again.

[RailRunRob]

3 hours ago, RR503 said:

Finally, if you just build local stops far enough apart, you can get near-express speeds without the extra cost of express tracks. I'd say just do that. 

Yep, Defiantly feel you skip a few stops the old line took.  With all the development going on at the waterfront wonder if Bruckner Blvd would be on the table for a stop?  Or at least build on the southern side of 138 with exits at 135 or closer to Bruckner.

[RailRunRob]

3 hours ago, RR503 said:

28 TPH according to the FEIS. So 14 each to 125 and the BX. 

And this with CBTC provisions accounted?

[RR503]

28 minutes ago, RailRunRob said:

And this with CBTC provisions accounted?

No — I think that’s working backwards from current/projected terminals and their capacities. Branching, and CBTC should get you a full 30, if not more. 

Edited February 3, 2018 by RR503

[Caelestor]

4 hours ago, Coney Island Av said:

I see we're talking about Bronx SAS expansions.

Well's here's how I think it should roll out.

Phase 1

The diverges from the at 125 St and runs across the latter to Broadway, with connections to the .

continues to 3 Av-149 St, where tail tracks will be left to extend the line further to Gun Hill Rd via 3 Av.

Grand St, Houston St, 14 St, 42 St, 55 St, 3 Av-138 St, 3 Av-149 St, and 161 St-Morrisania will be 4-track stations, with provisions for SAS express service.

Phase 2

is extended to Gun Hill Rd, and is extended to Co-op-City. A cross-platform transfer will be available at Gun Hill. Non revenue tracks will be made to the Concourse Yards.

Provisions for an extension via Lafayette Av to Throgs Neck will be left at 163 St, just north of 161 St-Morrisania.

A third track is installed, allowing peak express service on 3 Av. Express stations north of 161 St are E Tremont Av, Fordham Plaza, Bedford Park Blvd, and Gun Hill Rd. The rest, 167, 170, Claremont, 183 St, and 204 St will all be local stops.

As already stated, there's no need for the third express track if the 3rd Ave Bronx segment is only running at half capacity due to the 125 St branch. Also, the  should be running to 125 St and the  into the Bronx.

The  and  need to swap terminals. The one-stop extension of the  is to give North Bronx riders a 30-minute ride to Midtown vs 50 minutes on the , and also to divert riders away from the overcrowded IRT lines. Given that the ridership of the Bx12 is an order of magnitude higher than the Bx28/38, the  should turn east on Fordham Road and run straight to Co-op City. 

Overall, the SAS stops in the Bronx would be 3 Ave - 138 St, 3 Ave - 149 St, Melrose Ave - 161 St, 167/168 Sts, Claremont Pkwy, Tremont Ave, 180 St, Fordham Plaza, Crotona Ave / Southern Blvd, White Plains Rd , Williamsbridge Rd , Eastchester Rd, Co-op City.  The pricier alternative is to terminate the  at Fordham Plaza, and replace the Bx12 with a full  extension to Co-op City with additional stops at Grand Concourse   and University Ave.

 

32 minutes ago, RailRunRob said:

And this with CBTC provisions accounted?

The FEIS didn't account for that, but personally I think the practical maximum capacity of a 2-track subway is 30 tph, since station dwells and recovery padding needs to be built into the schedule. Plans also had a 26 tph limitation at Hanover Square, but that could probably be easily rectified to 30 if SAS makes it down to Manhatta.

[bobtehpanda]

5 hours ago, RailRunRob said:

I understand that to a degree I'm sure a new 3rd ave line would skip a few stops the old route took. Including a more direct route to GunHill Station under Bronx Park. Skipping the old Williamsbridge station. You have the Concourse line tunnel already at Webster tie that in even if just for Yard Access. I guess my second question is how are you measuring marginal? I'm sure this could save 10 mins in the Bronx alone one way.  An hour 40 mins savings for someone between those two points a week is a solid measurement for some other projects. Note I stated 241to South Ferry or Gun Hill to South Ferry with the original 3rd ave line. This would give riders in Wakefield, Williamsbridge,  Norwood, Bedford Park and Fordham another major route to the Eastside of Manhattan beside the .. I could see some trips cut by 20-25%. I also couldn't see 149th as being able to hold major additional ridership as a transfer point, What's there now plus with the South Bronx resurgence and development. Spread it out.  Penny wise dollar dumb ... isn't the way to plan. Do the research view the full picture and then make the call.. Disengage gut reactions I think this is something that at least requires a look.

So let's talk about what I get marginal from.

Unlike most other subway extensions which I've proposed which tend to be in less dense areas of Queens with only feeder buses and no subway access at all, the Central Bronx is dense and has an existing subway+bus grid network. Let's take a look at ridership on the crosstown bus routes, which all generally tend to be around the same length:

161 St

Bx6 weekday: 24,642

168 St

Bx35: 17,651

170 St

Bx11: 14,269

E Tremont Av

Bx40/Bx42: 25,454

180 St

Bx36: 30,474

Fordham Plaza

Bx9: 27,175

Bx12: 48,124

Bx22: 14,690

Bedford Park Blvd

Bx26 : 7,988

Gun Hill Rd

Bx28/Bx38: 15,750

Bx30: 9,680

 

All of the crosstown streets south of Fordham Plaza deserve a subway stop. So you're going to roughly have the same stop spacing as the Concourse local. Let's measure comparable travel times at 7AM on a Monday, from Fordham Road to 161 St:

 - 11 minutes

local - 12 minutes

local - 16 minutes

So we know that the Concourse local is 4 minutes faster to travel the same amount of distance as the WPR local. However, the express also takes 16 minutes to get to Third Av from Pelham Parkway. So the maximum time savings for someone going to the East Side is only 4 minutes, assuming the SAS train can instantly teleport itself from 161 St to 149 St. This is nothing to write home about.

Keep in mind that people also hate transferring. MTA assumes, relatively liberally, that people will tolerate 1.75 minutes of extra travel time rather than save 1 minute. So the train would have to be 2 minutes faster to get anyone to move tushes. And that includes the time it would take to walk to the other platform. So your ridership base is basically limited to bus transfers and the walkshed.

Given that no one is going to transfer from north WPR to the SAS, the ridership north of Fordham Plaza on crosstown buses is nothing to write home about, half the catchment area is parks, and the gap in subway coverage there is very small, I see very little marginal benefit of having the subway terminate north of Fordham Plaza. You could make a case for east, but that's another story for another day.

[RailRunRob]

1 hour ago, bobtehpanda said:

So let's talk about what I get marginal from.

Unlike most other subway extensions which I've proposed which tend to be in less dense areas of Queens with only feeder buses and no subway access at all, the Central Bronx is dense and has an existing subway+bus grid network. Let's take a look at ridership on the crosstown bus routes, which all generally tend to be around the same length:

161 St

Bx6 weekday: 24,642

168 St

Bx35: 17,651

170 St

Bx11: 14,269

E Tremont Av

Bx40/Bx42: 25,454

180 St

Bx36: 30,474

Fordham Plaza

Bx9: 27,175

Bx12: 48,124

Bx22: 14,690

Bedford Park Blvd

Bx26 : 7,988

Gun Hill Rd

Bx28/Bx38: 15,750

Bx30: 9,680

 

All of the crosstown streets south of Fordham Plaza deserve a subway stop. So you're going to roughly have the same stop spacing as the Concourse local. Let's measure comparable travel times at 7AM on a Monday, from Fordham Road to 161 St:

 - 11 minutes

local - 12 minutes

local - 16 minutes

So we know that the Concourse local is 4 minutes faster to travel the same amount of distance as the WPR local. However, the express also takes 16 minutes to get to Third Av from Pelham Parkway. So the maximum time savings for someone going to the East Side is only 4 minutes, assuming the SAS train can instantly teleport itself from 161 St to 149 St. This is nothing to write home about.

Keep in mind that people also hate transferring. MTA assumes, relatively liberally, that people will tolerate 1.75 minutes of extra travel time rather than save 1 minute. So the train would have to be 2 minutes faster to get anyone to move tushes. And that includes the time it would take to walk to the other platform. So your ridership base is basically limited to bus transfers and the walkshed.

Given that no one is going to transfer from north WPR to the SAS, the ridership north of Fordham Plaza on crosstown buses is nothing to write home about, half the catchment area is parks, and the gap in subway coverage there is very small, I see very little marginal benefit of having the subway terminate north of Fordham Plaza. You could make a case for east, but that's another story for another day.

Your Kun-Fu is solid but incomplete. Feeder Bus lines are definitely part of the equation but these still the margin of error with Matrix of ridership on these routes. Okay, I'm riding the BX42 from Brucker and Tremont to where? Westchester Square? But it's still measured as total route ridership but doesn't feed to the 3rd ave corridor . Starting with what I know to be true I know there's over 11 million riders per year using the WPR north of GunHill. So I'm not sure what studies you've based your conclusion that people wouldn't transfer from a GH or even Burke Ave transfer point.  Second and your correct in stating population density because I'm looking at that as well how many people live within a half a mile of stations north of Fordham as well as the WPR line bus lines factor in right in after that. Norwood, Bedford Park, Wakefield... Westside people Eastside people and now Extreme Eastside?? Lastly, I'm asking myself where are people are people going? Rider matixs "Karen Lives near the Nereid ave Station and works at Bellview this new service would cut 30 mins each day" How many Karens are out there? Could this create new Karens? There are more dimensions than just using current data.   And I'm looking at the peaks of the old 3rd because the population is exceeding 1940-70 levels housing density less? more?.. may be something there all the be factored.   I get the Bronx comparisons in A/B times.  Peak WPR service is never 16 mins from GH to 149th. Merge points like Jackson come on. Plus off-peak and weekends I'd like Extreme eastside service yes thank you. Fordham Plaza, BedfordPark (BG) and then GH or even Burke. CG Yard access and call it a day.  Without understanding, rider patterns were both guessing not the way I was taught to go thru the process. All I'm saying is conduct the study and don't write it out just yet.
 

Edited February 3, 2018 by RailRunRob

[bobtehpanda]

3 hours ago, RailRunRob said:

Your Kun-Fu is solid but incomplete. Feeder Bus lines are definitely part of the equation but these still the margin of error with Matrix of ridership on these routes. Okay, I'm riding the BX42 from Brucker and Tremont to where? Westchester Square? But it's still measured as total route ridership but doesn't feed to the 3rd ave corridor . Starting with what I know to be true I know there's over 11 million riders per year using the WPR north of GunHill. So I'm not sure what studies you've based your conclusion that people wouldn't transfer from a GH or even Burke Ave transfer point.  Second and your correct in stating population density because I'm looking at that as well how many people live within a half a mile of stations north of Fordham as well as the WPR line bus lines factor in right in after that. Norwood, Bedford Park, Wakefield... Westside people Eastside people and now Extreme Eastside?? Lastly, I'm asking myself where are people are people going? Rider matixs "Karen Lives near the Nereid ave Station and works at Bellview this new service would cut 30 mins each day" How many Karens are out there? Could this create new Karens? There are more dimensions than just using current data.   And I'm looking at the peaks of the old 3rd because the population is exceeding 1940-70 levels housing density less? more?.. may be something there all the be factored.   I get the Bronx comparisons in A/B times.  Peak WPR service is never 16 mins from GH to 149th. Merge points like Jackson come on. Plus off-peak and weekends I'd like Extreme eastside service yes thank you. Fordham Plaza, BedfordPark (BG) and then GH or even Burke. CG Yard access and call it a day.  Without understanding, rider patterns were both guessing not the way I was taught to go thru the process. All I'm saying is conduct the study and don't write it out just yet.
 

Anyone on north WPR can get on a , which is a one-seat ride. Unless the person is getting on directly at Gun Hill, they'd have to do a pretty inconvenient, non-cross-platform transfer. In fact, it'd probably be a long multiple-level transfer similar to the one at Jackson Heights, since there's a snowball's chance in hell that we're building new elevated track in 21st century NYC. People really hate transferring. Look at the abstract to see multiple studies where a transfer is equal to walking five-ten more minutes to the station.

If you want to throw out nonsense hypotheticals because it doesn't fit your narrative, go ahead. The best proxy of future transit demand is existing transit demand. Quite frankly, if activity nodes like the ones you're suggesting would be created by a new subway line, they would've been created by the old elevated in the much denser, more populated, Manhattan of the more Manhattan-centric world of the early 20th century. We don't see similar activity nodes around 33rd St on the Lex, for example.