• That's part of the idea behind 20mph limits rather than zones. Limits don't require vertical deflection (which was always built into 20mph zones to be 'self-enforcing'--obviously, while it's still annoying, it also led to cars with much better suspension).

    As for the annoying pseudo-mini-roundabouts, they're the consequence of more money being granted to councils under Local Safety Schemes funding where they introduced mini-roundabouts, on the grounds of their (alleged) better crash record (depends on location, and is certainly not likely where a white circle is merely painted into the centre of an ordinary priority junction). This is no longer the case, and as a result you see a lot fewer of them implemented these days.

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