I'd agree that at least in this case the manufacturers of self driving cars would have the incentive to maintain buffers. They'd be on the hook for lawsuits. B

I'd agree that at least in this case the manufacturers of self driving cars would have the incentive to maintain buffers. They'd be on the hook for lawsuits. But they aren't the only players in the system. Traffic is a political problem, and how politicians react to traffic issues regularly becomes a campaign issue. I have no problem imagining a world where a politician campaigns on requiring self driving car manufacturers to standardize on rules that reduce traffic.