I rented a car that had active cruise control and lane assist. I drove most of the way from Oakland to San Jose with out touching any of the controls, except ma

I rented a car that had active cruise control and lane assist. I drove most of the way from Oakland to San Jose with out touching any of the controls, except maybe the accelerator once or twice. But? I got to my destination exhausted and in a little pain because I had sat tensed up ready to take the controls again at a moment's notice. Partly that's because these features are not intended to be a complete self-driving solution. But partly it's exactly what you said - I wouldn't trust it absolutely anyway and would want to stay alert. It's easy for me to stay alert when I'm driving and not just supervising.