> The human accident rate is about one per 500K miles, so if they were able to get in that range, then yes, they would have succeeded; drivers would be able to stop paying attention to the road without putting themselves and others in danger.

Unfortunately, I expect that automation will be held to a higher standard than human drivers, rather than the same standard. When an accident happens, people want to know who to blame, and an unimpaired human driver gets somewhat more latitude for a genuine accident, while a piece of software is always going to be perceived to be at fault (which it may well be, even in a situation where a human wouldn't be considered to be). And conversely, people (somewhat validly) want to have more control: every driver thinks they're above average, and the software won't be as good as their accident rate, and if something happened at least they were in control when it happened.

I don't necessarily even think those are incorrect perspectives; we should hold software to a high standard, and not accept "just" being as good as human drivers when it could be much better. But at the same time, when software does become more reliable than human drivers, we should start switching over to make people safer, even while we continue making it better.

(Personally, I wish we had enough widespread coordination to just build underground automated-vehicles-only roads.)