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xkcd #2842: Inspiraling Roundabout
(imgs.xkcd.com)
Alt text:
Look, I just think we need to stop coddling those hedonistic roundabout hogs who get into the inner lane and circle for hours, wasting valuable capacity.
No, it's like saying expecting a tribesman to use a computer is crazy.
I'm American and I've used roundabouts. Plenty of them have poorly placed signs that confuse people.