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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.
The center should put you on an out-spiraling bridge that feeds traffic back into the outermost lane. Then even the most indecisive drivers are accommodated. Or just a deep pit of punishment.