Instead of trying to give everything a different name to ensure everyone is confused, why don't they just call it a subway?
It will be grade separated and relatively frequent so this is what the rest of the planet would call it.
Anyway, it's { and RERs success come down to just one thing..........the fares. if this is just another GO service than the ridership levels will be horrible. Just look at the UPX which is essentially RER running every 15 minutes all day each way and it serves 2 stops with GO fares and the ridership level is pathetic especially considering it connects the 2 biggest employment areas in the GTA.
I don't know why ML thinks RER will be any more a success than UPX isn't. ML keeps saying people will pay for the extra convenience and the UPX provides a clear that they won't. Just because the service isn't there doesn't mean everyone is all of a sudden going to get a raise so they can afford to take it.