I agree that there is no valid reason, in law, for exceeding the speed limit.
But, other than ease of policing, there is no valid reason IMHO for some of the blanket speed limits we have.
We can probably all think of situations we have witnessed where certain drivers, perhaps taking The Duke of Edinburgh as an example, are not even safe at the speed limit whereas an advanced driver, in their prime, in a modern car would be perfectly safe above the limit.
But a speed camera can't tell a safe driver from a dangerous driver so we have to abide by the law, however broad brush it might be.
