One doubts Bruce Springsteen realised that, when he shoved that scarlet baseball cap in his right rear pocket for the Born In The USA cover shot, for a broad swathe of his fellow Americans it was broadcasting a taste for, shall we say, ’five finger fun’. The Boss probably wasn’t au fait with his handkerchief code -- a form of sexual semaphore developed in the late 1970s to colourfully advertise your predilections on your sleeve. The code’s origins date back far earlier, to square-dancing San Francisco miners during the California Gold Rush. For the (by necessity) all-male assemblies,