a car accident is good for economic growth. Think about all the people who are employed when you drive past a motorway pile-up: the police to investigate, the fire brigade to cut the people out, the road cleaners to wipe it up, the MOTs, the refits. And if you’re really, really lucky there's an undertaker getting a job too. But you don’t see a car crash and say, 'Hooray! Things are looking up!'. Not unless Jeremy Clarkson’s in it.