Ian McGeachie annoyed a lot of people in Glasgow, years ago, when he took off for London and became The Folksinger John Martyn. Bad enough changing his name, but sticking a "y" in for an "i" - well I'll be knocked down, hog-tied, horse-whupped, dipped and double-dipped in dog shit, as Mick Broderick of the Whistlebinkies used to say.