If you have an idea for how, bearing in mind the constraints along Bay Street in respect of grade, geology, the PATH, utilities etc., a heavy rail tunnel could be added to it while still somehow being part of the GO system, be my guest and show your work.
I did not ask anyone to tell me how something was possible. Someone said "no tunnels are needed" and I gave some reasons we might build some in
decades. You then suggested that don't take criticism well, and then sort of implied this wasn't possible because we currently have a dysfunctional transit building apparatus and suggested that I was either naive or baiting people.
I spend lots of time talking about our dysfunctional transit building apparatus. That apparatus is still building a new subway across the downtown core.
"Heavy rail, rapid transit, subway, mainline EMU" is all meaningless in a future GO context where we potentially use EMUs etc. (these trains would be shorter in length and height, and would have performance similar to a subway train) I mentioned
in the post you quoted that this was in a far off future where we may build some infrastructure which is specific to electric trains, which can and should be just as nimble as subway rolling stock - which you can see in Munich, London, Melbourne, etc etc ad nauseum.
Building a tunnel
roughly along Bay street is not easy, but it's hardly unprecedented globally, and even in Toronto we are building longer tunnels for the OL which deal with the path, utilities etc. might a tunnel be deep? Would it not literally turn north up Bay
at present day Union station? Sure, but it's hardly impossible
if we get our house in order. Munich is building their second S-Bahn tunnel, Berlin is doing another cross city tunnel, Melbourne has it's loop and a new tunnel, Tokyo has various tunnels. etc etc etc.
Anyways, none of that matters, because it seems you personally have a bone to pick with me and found me to be "downloading" work onto the forum. I'll shut up and not reply further as suggested by
@Northern Light .