Ken is getting harshly berated for a mistaken judgement of a situation that might never occur during the reffing career of many referees. He assumed that Karl was using the cueball as a measuring device and by doing so he WAS committing a foul. But when he discovered that GWAPO was legitimately placing the BIH where he wanted to play it from as his next shot then he changed his decision (but only because it was the right thing to do) and the way that Boyes executed the shot confirmed that. Many players do not realise these infrequently invoked rules. I once saw Rodney Morris place a rest (rake) on the table and then place his cue on top of it. He then walked to the other end of the table and looked at the equipment that he had placed there. The referee called foul because he considered the player was using the accessories as a 'measuring device'. This was in a World 9 Ball Championship and it cost Rodney the match. He almost certainly wasn't using the trick to cheat the rules but the referee was of the opinion that this might be a possibilty and made the call accordingly