Because Colt didn't really become team-lifting great until his junior season. Colt was great his freshman season, but he was also playing with the national championship squad. Colt had a dip his sophomore season when he left. Then he had that south america jesus trip he took between his sophomore and junior seasons when he went down mexico way and rubbed some Tijuana-magic on his bicepts and became other-worldly.
And also because Colt and Vince aren't our standards, they're literally the best we ever had. Like, it's super cute and all to go out there and demand every QB that comes through is literally the best ever, but that's not realistic and will just lead to you having angry diarrhea on saturday nights.
Clutch on 3rd downs, too. It made them basically unbeatable because whenever they needed an improbable catch, they'd get it. That's what made the OU game so great, OU was actually firing on all cylinders for most of the game. That meant every possession for Colt was do-or-die, and he came through on every drive after Shipley's kickoff return. That game was magical for Colt McCoy, the absolute best he ever was.