Not necessarily useful
Sounds like a bad idea to turn OFF the self driving when there isn't anyone holding the wheel.
Turning it ON, with some kind of alarm would be a better option.
Anyway, this is all bass-ackwards.
If this was about safety, the human should have to drive all the time with the Autopilot kicking in only if they do something blatantly stupid (with the ability to do a conscious override, a la stability control).
Biting the hand that feeds IT
