Re: PT Barnum...
"I'd want to see about a decade of driving results that are substantially better than the typical Human before I accepted any claim out of his gob."
It isn't that hard to drive better than a human most of the time, and it isn't that hard to drive better than most humans.
The bigger problem is programmatically adhering to rigid rules such as "PEDESTRIANS WILL NOT CROSS THE ROAD EXCEPT AT DESIGNATED POINTS", which sound fine to wetware but when interpreted literally result in automated killing machines roaming the streets mowing down pedestrians who dare to try.
Thankfully only the USA and a couple of other authoritarian countries have such "car is KING" type rules, and even then, "common sense" gets applied by human drivers. A machine programmed with such rules that runs into a parade and marching band won't stop for them, which will make for a whole new interpretation of American (road) Pies.
Google have got it pretty much right. Uber utterly fucked up.