Whether it is power line or another AP or an extender, I think an issue still remains - the handoff of a device from one AP to the next. This morning, the car was (presumably) happily on my extended wifi network. My phone OTOH was still talking to my house AP (weakly). I summoned out of the garage, and at a certain moment, the phone jumped to the stronger AP (extended network). At this moment, the app on the Tesla app on the phone changed to STOP (as it lost connectivity) but the car kept rolling. I'd guess a good 5 feet (was a bit caught off guard, so memory may be less than accurate). There was nothing in its way/no risk, so it wasn't a big deal this time, but that could be a big deal if it meant rolling onto the street or into something that sonar didn't detect.
Someone mentioned a possible reason Canada doesn't get fob control may be that our fobs/cars have mandatory immobilizer technology. Can anyone confirm if CAN cars have this immobilizer tech and USA cars don't? I would think tesla would keep the cars as similar as possible (granted things like DRL are different, but that I believe is just software).