Look, there are some things I really like about your reply, and I applaud your approach to this.
My question is this: If you are the pilot, how do you communicate with the FSD to have it execute the maneuvers? What is the command interface? What is the level of "manouver" ("drive to the grocery store" vs "angle the front wheels 7 degrees to the left to initiate a left turn")
> "there were a couple of times I expected [the loaner] to stop and it didn't."
So these times, in your car, are circumstances where you expect the car to stop. Did you (as the pilot) tell the car to execute the stopping manouver?
> Your #1 job, and the thing that can kill you, is thinking that autopilot is engaged when it isn't and running a red light "
What if it is engaged and still decides to run a red light? Or to suddenly brake to a full stop on a highway so you get rear-ended?