Kessler looked bad. Agreed. But your claim that the headbutts didnt affect the outcome is bull. Watch the fight again. Kessler couldnt see from round 5 because of the cuts. He says this to his cornerman. Kessler still looked sloppy though, but lets stay to the facts and what really happened.
You are correct. Looking nervous at a weigh-in means nothing for Froch. He looked really nervous at the weigh-in against Pascal and went on to win a pretty wide decision in their war.
I usually never buys into staredowns, but Froch was worryingly looking around after that intense staredown. Kessler looks mean and ready to drop bombs.