Indeed, and not only that, Elon Musk's example of Autopilot supposedly saving lives that he famously tweeted a while back was manual driving + active driver assistance in the form of automatic emergency braking (which is supposed to become mandatory on new cars at some point). It happened in conditions far outside what Autopilot was capable of actually driving in.

I think that we'll only turn over driving to a computer (for reals) when safety systems are good enough to prevent most accidents. I think we'll keep the safety system separate from the drive system.

Perfecting safety on human drivers first is the way to go and will most of the risk of lettings computers drive.