FWIW...here's the old 1943 NY Central division maps:
http://www.canadasouthern.com/caso/maps.htm" onclick="window.open(this.href);return false;. Also includes a bunch of property maps, though only a few of those are in the affected divisions.
1. Electric Div.:
http://www.canadasouthern.com/caso/imag ... ectric.pdf" onclick="window.open(this.href);return false;
2. Hudson Div. (i.e. diesel territory, Croton-Harmon to Albany):
http://www.canadasouthern.com/caso/imag ... hudson.pdf" onclick="window.open(this.href);return false;
3. Mohawk Div.:
http://www.canadasouthern.com/caso/imag ... mohawk.pdf" onclick="window.open(this.href);return false;
4. Syracuse Div:
http://www.canadasouthern.com/caso/imag ... racuse.pdf" onclick="window.open(this.href);return false;
5. Buffalo Div.:
http://www.canadasouthern.com/caso/imag ... uffalo.pdf" onclick="window.open(this.href);return false;
Electric Div. pretty much what it is now, except for >4 tracks from SD to some indeterminate point north of Yonkers.
Hudson diesel territory, as mentioned previously, was a 4-track RR from Croton-Harmon to Rhinecliff everywhere except for the 2-track-only rock cuts between Peekskill and Garrison currently occupied only by the one-round-trip daily Manitou flag stop. Then double-track north of the present-day MNRR district limits at the Dutchess County line up to Albany.
Entire Mohawk Div. from Albany-Rensselaer to the division post at Kirkville was quad-track.
Syracuse Div. had some tri-track in immediate downtown because of the way the branchlines peeled off and merged. Otherwise full quad end-to-end past the division post at Depew. That downtown triple pinch, however, looks like it was quadded sometime after 1943 when the West Shore Line midsection was truncated through downtown. It's presently quad everywhere except for the 1750 ft. where it passes under I-81, over NY 370, and through the wye with the St. Lawrence Div. I assume because I-81 construction rebuilt the section that underpasses the highway viaduct with a smaller bridge over NY 370. It's all wide open space underneath that viaduct, so can't imagine there'd be any physical constraints on widening under highway no-man's land.
Buffalo Div. was full quad from Depew to downtown where the Niagra Branch and Main Line to Erie diverged.
So, yeah...like Noel suggested, this was a full 4-track railroad the entire length of the WLR to Buffalo. And unless there was post-1943 encroachment along the way or more land grabs for adjacent NYDOT highway construction there's no reason it can't be refitted to full quad once again. 2 passenger x 2 freight, freight on the northside where the yards are, passenger on the southside where the stations are, track-sharing only where CSX needs to reach its random assortment of south-facing customers on its locals, no intermingling needed on anything thru-and-thru. All it takes is money, and NYS not attempting to cut corners by regressing to backdoor cuts of more track sharing...which CSX is wholly justified at being vigilant/skeptical about. If they want this done, they're going to have to do it right and pretty much replicate the old NY Central track capacity verbatim the whole route Spuytien to Buffalo. No going cheap in Metro North territory if they want a peaceful coexistence; they need Track 5 and a staggered merge from SD to Yonkers, they need at minimum Track 3 and pre-provision for dropping in Track 4 with later growth everywhere in diesel commuter rail territory except the constrained (and station-less) rock cuts. And they need a full quad-track railroad on the WLR for peaceful coexistence with the freights.
It can be done, because it WAS done and the ROW property lines on at least 95% of this route haven't changed in the last 70 years. This is all a matter of follow-through on NYS's part and not making assumptions that they can introduce stealth cutbacks to the buildout and squeeze their landlords MNRR and CSX with ever-shrinking capacity as the plan advances to design. Which you know WILL happen and put the various roads at loggerheads again if the political climate in Albany doesn't get a whole lot less cynical about this.
Compared to CAHSR, NYS has it easy building a 110+ MPH cross-state high speed line pushable to 125+ with later electrification layered on top on the 2 WLR passenger tracks. They don't have to carve any new ROW, and hardly have to widen any existing ROW except at the stops that need bigger/wider station facilities straddling the existing track real estate. They just have to pony up the resources and stop cutting their own legs out from under them and their RR partners by pushing a slow and cynical whittle-down of the plans. That's it. Do what has to be done, and push the regime in Albany to walk the talk for a change.