I do realize this post is quite old but as I haven't had logged into UT for a while I thought I'd respond now.
May I ask you how many future stations you envision along the Don Branch?
On the Don Branch itself? Not really any - other than maybe Danforth.
The issue is more for north and south of that. At S-Bahn stop spacing you would probably stop at Gerrard, East Harbour-ish, and Sherbourne at least, and north of that somewhere in Thorncliffe and at Eglinton. That's not to mention that any sort of Midtown line which would use that corridor and stop frequently. With that, HSR using that route is clearly untenable.
Again, how many future station stops do you envision between Union Station and the Belleville sub? If we assume EMUs with 3 stops at Kennedy, Scarborough and East Harbour (and reasonably fast track speeds east of East Harbour), then their superior acceleration and much shorter dwell times should mostly compensate for the 2 additional stops compared to an ALTO train stopping at Kennedy only.
I said in my original post 4-5 additional infill stations? With 5-10 minute frequencies? Even that would be wider stop spacing than a typical S-Bahn, to allow for higher average speeds (in light of Toronto being a geographically large sprawling city). If you want specifics something like Sherbourne, East Harbour, Coxwell, Main/Danforth, Warden, Scarborough Jct, Kennedy, Lawrence, Ellesmere would seem reasonable by S-Bahn standards. Even if these stops are not envisioned presently, putting HSR on any corridor which cannot fit express tracks is precluding or significantly complicating any future attempts to achieve S-Bahn-like service standards.
I’m somehow skeptical of a third and fourth track between Guildwood and Pickering.
As other posters have responded to this I won't repeat them.
I guess this is where European (satellite stations should serve secondary hubs which are served by high-quality transit corridors preferably not already serving the main hub to ease access by transit) and North American intercity rail service planning ideology (satellite stations should be placed next to a busy Highways with giant parking facilities, to ease access by car) clash. You won’t overcome car-centricism by pre-emptively obbeying to anticipated car-centric demands.
This seems like a ridiculous statement to make when my entire original post was about how to route HSR to accommodate S-Bahn levels of regional rail service as opposed to what now appears to be the current plan of GO service continuing to skip past central parts of Toronto without stopping and with frequencies only somewhat better than the Long Island Rail Road.
Car access to Pickering is obviously a side note to the broader point that Pickering is much more accessible to people in Durham and to some extent York (via transit or via car). Stopping in Durham Region has much less to do with "North American intercity rail service planning ideology" and far more to do with the fact that by the time anything resembling HSR is built over 1 million people will live in Durham Region. And Pickering station, other than being car accessible, is *also* one of if not the most transit accessible locations in Durham Region, and will soon densify in a similar way to MCC and VMC. If Nauen (~15km west of Spandau, ~30km west of Berlin, a similar distance as Pickering) was a region with 1 million people or even 500,000, there would obviously be an ICE stop on the Berlin-Hamburg and/or Berlin-Hannover lines there, just as places like Wuppertal or Bochum are served by ICEs (both of which are similar in population to just Western Durham). Finally, nothing about stopping in Pickering precludes stopping in Scarborough as well (either stopping at both, or alternating between them), only that Scarborough Junction is a somewhat worse Scarborough station than Kennedy (something which I also mentioned in my original post, but something that can be mitigated with infill stations and better service on the Stouffville line).
As a side note, the threat that “they will just drive to the Airport if you don’t stop close enough to them” is much less credible in Durham than, say, York, Peel or Halton…
Yes, that's why I said
York and Durham. Besides, it's also quite competitive to just directly drive to Ottawa or Montreal from Durham Region.
