> "the resulting congestion required law enforcement to manually manage intersections"

Does anyone know if a Waymo vehicle will actually respond to a LEO giving directions at a dark intersection, or if it will just disregard them in favour of treating it as a 4 way stop?

I suddenly find that I really want an answer to this as well because I'm now imagining what might ensue if one of these attempted to board a car ferry. Typically there's a sign "turn headlights off", you're expected to maintain something like 5 mph (the flow of traffic should never stop), and you get directed by a human to cross multiple lane markings often deviating from the path that the vehicle immediately in front of you took.

Your scenario seems to have a lot of overlap with a construction worker directing traffic around a road construction site. I have no idea if Waymo is any good at navigating these, but I am sure there is a lot of model training around these scenarios because they are common in urban driving environments.

This was found to be one of the early challenges of self driving: reading traffic signal gestures of traffic agents. It does it. But the jury is out if it does it well.