The alternative was to behave like a stage cockney from the Dick Van Dyke tradition, and, almost as common as faux aristocrats, were public schoolboys talking in a London “street” slang that doesn’t exist outside Guy Ritchie films. During my time in New York, I came across dozens of these types, nearly all of them working for large investment banks on Wall Street. They’d figured out that the key to success across the pond is to conform to an Upstairs Downstairs view of Britain in which you’re either at the top or the bottom of the social pyramid. If you were somewhere in the middle, like me, Americans simply couldn’t work you out. Graydon Carter, the editor of Vanity Fair, once told me I was like a British person born in New Jersey - that is, ordinary rather than a pantomime Brit from central casting.