I haven't read the entire thread, but in my experience on popular "Rouge" routes to the US (i.e. SFO, LAX etc.) I really wished the folks at AC enforced carry-on more strictly.

I get that families are trying to take their kids to enjoy their first Disney holiday, but there really is no need for 20 families struggling to get their supposed "carry-on" while complaining there is no room to fit them in the overhead bins. The worst is seeing people struggle to lift their luggage up top when clearly, it is overweight and over sized.

Gah!