Originally Posted by Nepean
...The LRT is a commuter line akin to Paris' RER train system...
not sure where you're coming from with the RER analogy. The RER is the "Réseau Express Régional". GO, AMT's Train de Banlieu and Vancouver's West Coast Express are the closest examples we have to the RER: heavy rail commuter trains that run largely on existing rail corridors to connect stations within far flung suburbs to a very limited number of stations in the core of the city. The difference with the Canadian ones is that most don't provide the all day frequent service using electric trains that the RER uses to complement (and relieve congestion on) the Paris Metro.
RER trains are NOT LRVs, they're big, heavy, high-capacity trains (e.g., double-deckers on the RER-A
D). The trains run on lots of track, many stations are at least triple tracked so express trains can bypass them, and there are lots of branches on the lines as they cover a huge network. The trains usually only stop at one station central to each suburb/town, and stop at a very limited number of stations in the Paris core, either for correspondence to Metro lines, or to serve an area without a nearby metro line (e.g., Luxembourg on the RER-B, the newest RER, the E has been planned to similarly augment the metro, but that line's expansion has been slow to progress)
If we were building something on the RER model, we would be buying dozens more O-Train type vehicles (with the intention to eventually convert to electric, like GO and AMT plan to do, for more efficient service), and we'd be running them as often as possible, on all of the existing tracks in the region, as far as possible east and west as well as south (presumably double/triple tracking stations to reduce headways). Downtown, we'd have a short tunnel to link Bayview to Union station, with at most one stop in between. That would be it. Also, if we were doing like France, we'd probably be converting the Transitway to a driverless metro (Siemans Neo-VAL would be a leading technology choice, I bet -- see the planned Ligne-B in Rennes, pop ~250K), and of course, we'd be adding more stations and building above the line wherever possible on top of all that, we'd probably be digging metro lines under Bank and Rideau-Montreal, as well as building tram lines to link the suburbs to each other, complete with nice happy new town squares all along those lines.
What we're planning is a strange camel-type creature, taking LRT/Tram hardware, using it to serve subway/metro capacity in the core, with the intention of running it more like a commuter line for the short branches outside of the core (i.e., avoiding development areas and stopping as little as possible to provide as fast service as we can to far flung suburbs, but suburbs which we won't actually be running trains anywhere near for decades, if ever). It's not commuter rail because it doesn't go anywhere near commuting suburbs, or use heavy commuter trains. But it's not LRT either, since it's turning it's back on development areas, running long trains, and skipping along too long between stops in the already-intensifying areas. And it's not a metro, because we want to have drivers, we don't want to run under the densest parts of town, hit big secondary destinations, and we don't want people to use it for local connections from one urban neighbourhood to another.
whew, that got long.