I've been giving this idea a lot more thought lately, and given that traffic congestion is way more severe northeast of Jenkintown than it is in the northwest direction, I think the case can be made for intensifying service on the Neshaminy end, even at the expense of Glenside turns. And Glenside station is an 8 minute walk from my front door. Of course, this means having to build and maintain a new interlocking and connecting track at Ayres. Another option would be to go with the proposal of a complete interlocking at Somerton while abandoning Neshaminy Falls. Then we could have Somerton turns in place of Glenside turns. But adding another 30 minutes to the round trip might not be worthwhile. And though there'd be more trains, there ain't a blessed parking spot available along that stretch, save for a dozen or so at Noble (which might have some TOD potential) so in order to realize any benefit, there would need to be parking decks at Bethayres, Philmont, Somerton, Forest Hills.. So maybe that's not such a great option right now. If only there was another unused railroad that ran to the northeast of th..OH YEAH! So I think the bottom line is either constructing the crossover and connecting track as per John Scott's proposal at the expense of Glenside turns, or rebuilding the line up from Fox Chase.
I think the Fox Chase routing still wins for several reasons: 1. Better cost recovery for Fox Chase and Southampton/Newtown trains, as they will be one and the same. 2. We can keep the Glenside turns, especially since they had infrastructure (Carmel South, Glenside siding) built and maintained for this purpose. 3. Not having to deal with the added environmental issues involved with building that connecting track on protected wetlands. 4. Maintaining a much simpler interlocking at Ayres with fewer moving parts.
Also, I don't think there's any guarantee that a terminal at Huntingdon Valley would draw much traffic off the surrounding roads. 232 & 63 is very congested during the rush, and assuming most of the potential riders are coming from the north and east of there, they're going to be making a left into this terminal among the throngs of cars heading to the Willow Grove turnpike interchange from the Fox Chase area. I'm not sure such an expensive undertaking will reap much of a reward in terms of easing traffic congestion on area roads, as much as having Southampton or Newtown trains running via Fox Chase would.
I can't remember if I've said it before, but the main line from Jenkintown - Tabor at the moment, according to my casual observations and back-of-the-napkin calculations, can handle roughly 10 trains per hour without slowing down following trains. At the moment, they run about 8 per hour during the rush. And since there's no appreciable capacity added when you get to NX, and there's 2 trains an hour from Fox Chase, the trunk is effectively full during the rush. I guess technically you could do the HV turns if you eliminated the Glenside turns, but it seems to me that it makes much more sense to run via Fox Chase, because we'd get to keep the Glenside turns, and you'd need to run Southampton/Newtown trains via Fox Chase anyway.