Let's assume that Greg Ward would have gotten injured middle of the game, week 1 against Tennessee Tech and was knocked out for the year. Do you really believe that Houston would be 11-1 right now? Obviously, they may have adapted and gotten over the injury and still salvaged a pretty good season. But, would they be 11-1 with Kyle Postma taking all of the snaps the rest of the way? If you say yes, I'd say you're crazy.
BTW, Postma seemed to be a pretty good QB in the Memphis game the week before the Uconn game, when he rallied the team from a 20-0 hole to beat Memphis. It's almost like those freshman/sophomore QBs are inconsistent from week to week. Which might be why it's hard to have a great season with one of them at the helm.