“Sam Johnson wouldve clobbered him one.”
Perhaps, though it is unlikely that Sam would have been stupid enough to make the crack about “oats for horses”.
He was notoriously anti-Scot, but if he knew you he would always make an exception. Boswell, his autobiographer, was a Scotsman and a close friend, but he had to put up with a certain amount of anti-Caledonian sniping.