I was very bullish on full self-driving. Now I think "guard rails" is the thing I'm hoping for. Your car actively tries to prevent accidents. Then, I think o

I was very bullish on full self-driving. Now I think "guard rails" is the thing I'm hoping for. Your car actively tries to prevent accidents. Then, I think once that's seen as working really well, I think what's next is that it will become prohibitively expensive to insure your car without keeping the guard rails on all the time.