The dominant decision tells you with certainty who is better.I'm not arguing it does. As I said, I can't really make up my mind either way. Gun to my head, I'd say a dominant decision win would suggest the better fighter, over an early KO. But it's not like a KO is a fluke. So again, hard for me to decide.
The one punch KO leaves uncertainty. But does not discredit the winner either, that would be a mistake to say that.
KO artists have to be judged on their consistency over many fights. Not on one single fight (like Joachim Buckley).