I agree that there's a tricky calculus involved in some scenarios, but I think there's a much wider domain of not-at-fault scenarios where autonomous vehicles should be able to surpass humans unambiguously. Example: an autonomous car being tailgated by a human-driven car, with a stop sign or light up ahead. Different braking patterns have different likelihoods of causing an accident.

Autonomous cars really have to be able to handle these scenarios at least as good as, and ideally better than, humans: there's not a complicated split-second balancing act to worry about.