Some years ago I was asked about piano burning by an American journalist. He had heard that the tradition had its basis in an edict issued in the 1920s or 30s that RAF officers should take piano lessons to improve their social skills, which had inspired such hatred that they eventually took their revenge on such instruments; was there any evidence for this? I could find none, and recalled that the early series of "It's a Knockout" had included races between two teams who each had to pass a piano through a hoop of (say) 2 ft diameter - clearly the quickest method involved sledgehammers... Might that have been an influence?