So get this.
Per Air Canada's website, to fly direct from Toronto to Paris is $709 (one way incl. taxes)
But to fly from Montreal to Toronto to Paris is $545 (one way incl. taxes)
This is all on the same day, same flight. Air Canada mystical pricing. Woot.
So the question is: Can one be a no-show for Montreal-Toronto to get the Toronto-Paris flight for cheaper later that day? Or would they cancel your entire itinerary if you were a no-show.