You're absolutely right, but it's a nailed-on certainty that Kettlewell will offer him a new contract, as I'm convinced he chooses not to acknowledge the things caused by his poor decision-making. For example, in his post-match interview, he stated that the defence was unsettled because he had to replace injured/knackered players, which is fair enough. However, he doesn't acknowledge that he unnecessarily unsettled the entire defence by trying to accommodate Butcher when it should've been a straight swap for Casey, allowing the remaining players to continue doing what they had been doing quite well. Some accountability and evidence that he is learning from his mistakes wouldn't go amiss here. Even the usually jolly bunch on P&B appear to blame today's capitulation on the manager, which speaks volumes. How many more defeats, poor in-game management, and questionable signings will it take before the fans turn on him en masse?
The man who brought Butcher on and unnecessarily rejigged the entire back three to accommodate him cost us the game. A lot more happened following that substitution, but many people on the forums acknowledge it was a turning point in the game.