Speeding kills, we’re told. But in the right circumstances, exceeding the limit is no bad thing. Take motorways: few drivers seem to stick to 70mph, yet most journeys are perfectly safe. Indeed, when I’m behind the wheel, I like putting my foot down as much as the next driver. Fortunately in the 30 years since I passed my test I’ve been pretty lucky; I’ve clocked up two or three speed awareness courses, but somehow I’ve managed to keep hold of my licence.