First takeoff he was in coarse pitch
Horrible performance is bad of course, what is worse in that situation would be the likely engine damage from detonation. I've done the testing, an O-470 operating at 28 inches MP, and probably 2000 or so RPM will be a very unhappy engine! I've seen holes melted in pistons from less. That is why, for all certified airplanes, moving all the engine control associated with power forward, will produce the greatest power, and least risk of engine damage (manual turbo engines notwithstanding). Know your plane, get some training...