Road Safety Bill [HL]

I wonder whether I am the only noble Lord present who does not know the   precise definition of a restricted road. Based on experience in my home in Clackmannanshire, I notice that there are a lot of signs which tell me that ““20 is plenty””. They tend to be in the housing schemes, at the Braes of Tullibody for example, or else they are around the primary schools such as in Clackmannan and are indeed backed up by speed bumps. That strikes me as a good idea. I get the impression from the debate on this amendment however that those ““20 is plenty”” signs are not actually legal at present and are only advisory. It would be helpful if that could be clarified.