Allan wrote:What PATH consider doing instead is installing switches between Christopher & 9th and between 14th & 23rd so they can route trains should there be a problem. Actually, it should be re-install because the H & M had switches there but when PATH took over they removed so they would not have to maintain them. Considering some of the situations they have with track work and occasional train breakdowns I am sure they wish they hadn't done it.
The switch west of 9th St. was taken out because PA-1 and later cars didn't have clearance there. Since that area is still in segmented rings (it doesn't switch to cut-and-cover untl 12th St.), ripping out some more ring segments was more than they wanted to deal with.
The 19th St. crossover dated from when the temporary end of construction was at 19th, and served the same function as the one in front of 33rd today. It was then mostly-unused until the original 33rd St. closed on December 26th, 1937 and service temporarily terminated at 28th St. I don't know if it had clearance issues with PA-series cars, but based on experience elsewhere in the system, it probably did.
When operating single-track westbound through Grove St. on the (normally) eastbound track, if the interlocking at the west end of Grove St. is set to return you to normal and you operate through there at the speed allowed by the signals, you can scrape the center wall while crossing over, depending on how much sway you have. It's usually at the back end of the train, so the engineer and conductor may not notice it. Most engineers will take it a little slower to avoid this. The opposite move (normal westbound into Grove, then crossing over) is a lot less common and I don't know if you can scrape there, but I'd assume so.