Robocars - Autonomous Drive, Self-driving, Driver-less cars

Exactly.

The caveats described are mechanical limits rather than human elements.

The scenarios are "Drunk person walking in front of car within the car's stopping distance".

I still reckon the car will act far more sanely with respect to everything else that is happening on the road at the time... the drunk person will definitely be hit, but the car won't have swerved across the road into oncoming traffic or mounted the kerb, etc.

I see it as a margin of error. Human = unpredictable and can escalate quickly. Roboto = To my knowledge, reliably predictable.
At least the robot car will stop after hitting me and dial emergency services.