[josef]

Then we can remove the barrier before 8th & Market and PATCO can operate all the way up to Chestnut Hill? Sold! (The tracks are standard gauge, so if BSL trains can operate up there, so can PATCO, muahah.)

Flippancy aside, I love the idea of using existing infrastructure for expansion. America obviously isn't in a "let's built cool new things" mode, and probably won't be for a very long time, so using what's there is great. It's what NJ Transit's done in New Jersey with the Riverline and the upcoming Glassboro-Camden line.

I don't know the specifics of the technical aspects, but the fact that you only have a choice of like 3 trains to get to work in the morning from a point served by public transit (on either CHW or CHE) within the city is insane. I always thought it'd be great to see the Ridge Ave spur actually built out the entire length of Ridge up to Manayunk, but this is a good plan too.