Yea so ? Harping on the 2% issues does not negate the benefit you have the rest of the time: It can swerve in microseconds, you cannot. How many times will your nail removal skills save you or your kids live compared to software that knows that rolling the car to the left have a 87.34 better chance of occupants survival that the head-on collision with the truck that just swerved in 0.4 seconds ago ?

Forget it, driver-less s cars will be the norm in the future. You won't be able to afford the insurance associated with a meat-driven car.

My nail removal skill will prevent gridlock on the road. If an auto-car gets confused due to a 2% issue, it becomes a brick, clogging the road. If multiple auto-cars do this in a city, the result is standstill.

You make it sound like people are gonna be strapped into their autonomous vehicle like Hannibal Lector. Seriously, a couple pieces of debris are not some thing where we go "oh crap, we're done, guess the whole city will just sit here all day."

Can it not drive around the tumbleweed? Or, if it's completely walled in by them, make an assessment of their density and likely harm caused, and decide to just run over them?

If we're crediting the car with being able to handle merging into a crowded multi-lane highway and dealing with idiot human drivers who don't indicate or hold lane position very well, it seems a bit odd to arbitrarily presume that it won't be able to identify non-hazards like said tumbleweed.