One of my friends talks about this skate park on Stevenson st, which is a cobblestone road in San Francisco. It's ostensibly a two way road, but with street parking, it isn't really. Or rather, in order for two full sized cars to fit, one of the cars has to go up on the curb. Waymo's don't seem capable of doing this (yet, on that street), and jam up that road whenever there's traffic on it. Waymo's has problems with that narrow SF street and any amount of traffic on it.