Re: "...situations that aren't covered..."
(I am a car driver but don't cycle nearly as much as I used to.)
Personally, I think people underestimate the flexibility of behavior shown by both motorists and cyclists. For instance, when overtaking a cyclist I notice things like leaves in his lane, and become alert for a swerve or slip of his wheels. I see human drivers creating their own rules in crowded merge lanes -- creating rules in a good way, as in "you take a turn and then it's my turn", with both parties doing what is expected.
Yes, I see violations of common sense, but I tend to think these stick in my memory precisely because the majority of drivers and cyclists do behave with common sense, especially when presented with a novel situation.
The law recognizes a "last clear chance" doctrine: even if a driver has the right of way, and is obeying the law and the rules of the road, he has an obligation to avoid accident if he can. I'm not sure how one writes an algorithm to mimic the unexpected and creative maneuvers a human driver might use at the last second to avoid accident. I'm not sure how existing case law around the "last clear chance" doctrine will be applied if, at that last clear chance before a fatal accident, a machine is controlling the vehicle.
OTOH, I am kind of sure that these things should be worked out, as much as possible, before very many autonomous driving vehicles are on the city streets.