Cyclists, unlike motorists or pedestrians, tend to notice other cyclists. When I was working as a bike messenger, Jon Snow was an almost permanent fixture of Gray's Inn Road, shuttling to and from the ITN building. I saw David Cameron, for all his eco-trumpeting, only once. He was going down Whitehall with the telltale wobble of the amateur enthusiast. There was a car following, though whether it contained a change of clothes and briefcase I couldn’t say. And then there was Boris Johnson. A regular pick-up from the Angel going to Burlington House on the Strand would send me down Rosebery Avenue, where I’d often see him emerging from Amwell Street. On a particularly slow and dismal day I chased him down and said: ‘Giz a job.’

