I agree akajonnyg, many times I am stuck behind a dawdler doing much less than the limit and they are weaving all over the road. The reason they are driving so slowly and all over the place is that their attention is elsewhere, either changing a CD, on a phone call or even talking to a passenger. I am not condoning speeding but I believe a speeding driver is more able to avoid a pedestrian than someone way under the limit who is not looking where they are going. This is where the replacement of traffic police by speed cameras is in my opinion a backward step, as a human can detect many more offences than a machine programmed to just take pictures of cars doing more than a set speed.