I think there is a potential for them to exceed human performance in all driving conditions. Machines can perceive and react much faster than humans, and once t

I think there is a potential for them to exceed human performance in all driving conditions. Machines can perceive and react much faster than humans, and once the perceptual and control problems are solved, all of them will become uniformly "good" at driving in difficult conditions. BUT (and there's always a "but"), the problem is exponentially hard, and it can't be solved with today's technology. I agree with you that widespread adoption will require modification of roadways, and potentially also segregation of autonomous and human-controlled traffic streams.