Hope you were joiking, and you are not that AC-centric! All AC, including Jazz, arrive T1. Thus, if you are coming from a Jazz or AC monopoly city (can we pronounce YGK, YSB, and on and on), or if you actually prefer to fly AC, you will arrive T1. Now, you want to fly on with CX or BA etc etc iinternationally, or AA, or DL etc etc transborder, or even a certain unamed domestic airline to western Canada, you will have to transfer to T3.

Gee, I guess that's why they built the cable car connection between T1 and T3! There are airlines other than AC!

However, you are right that arrogant AC is the only major airline that does not interline luggage at all.