As a long-time reader I have seen many emails appear over the years about speed humps, their effectiveness, and the side effects of their imposition, not only car drivers and their vehicles, but upon residential Property and the foundations of the road itself. I can see some of the benefits of your suggestions to counter speeding in your reply to B.D. of Ilkley. But surely motor vehicles could be controlled as they enter restricted areas in much the same way as a Formula 1 racing car can be controlled by an electronic gizmo once it enters the pit lane. Even today, we are able to substantiate by way of our satnavs when we are entering or leaving a speed restricted zone. Surely, one day the technology will be available for GPS location equipment within the vehicle to link it to the engine management system to bring about a progressive retardation upon approaching a controlled zone.