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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.
There's also simply no way of getting out once you're inside. It doesn't work even if it was used by just one car.
You'd have to drive the wrong way in a one-way street.
The joke is that you have to lane-shift to get out, the way you have to in most large roundabouts already.
Something people not used to roundabouts seem afraid to do, hence this is a design that "doesn't coddle them" because if they don't lane-shift, they end up in the middle.