We should increase speed limits on urban trunk roads to 40, and reduce them on urban non-A-roads to 20. That will slow down traffic on most urban roads, while probably having little effect on journey times.

And we should enforce the law. It brings the law into disrepute to have laws on the books that are not enforced. If you don't think you should get a ticket when you are speeding, you should call for speed limits to be abolished, not for speed cameras to be abolished.