Councils round the country have wasted mega-millions (as ever!) by splashing 20mph signs, with some road painting, in places that are quite pointless.
As for the claimed results, well, I'd have major doubts, I recall a news item that the Oxford Council claimed to have had a successful 'consultation', with majority approval for a Low Traffic Area concept -- which sounds good, but actually means that other nearby areas become Extra High Traffic!
This consultation was later shown to have been nonsense, the Council had apparently ignored the actual result, and just did what they wanted to. On the TV news recently, I saw that the same Council has repeated this jolly wheeze, a 'consultation' sent a resounding NO for their plan to introduce traffic charges (like the London central area ones), but they'll implement it anyway!! Doubtless if they'd had the result they really liked that would have well publicised, but why should the public there be paying for a 'consultation' that was completely ignored?? Can Councils be impeached?!