> I believe Waymo has had issues where several AVs occupied the same street after an event and blocked traffic because they couldn't decide what to do - they were waiting on each other to behave like a human.

You're thinking of some of the Cruise incidents like https://m.youtube.com/watch?v=kyAX28dapps .

> And a minor but still important caveat is that SF and Phoenix have modern linear grids

San Francisco has some amusing areas as well. If you look around the streets near Buena Vista park or even Twin Peaks, you'll see plenty of funky curves, six way "intersections" and so on. Lots of two-ways that are only lane wide.

Like the older parts of Boston and Cambridge, it's a holdover from the days of horses and the geography. That's where the paths were, people built houses, and now you've got to deal with it :).