From my perspective in The Zone.
That trip set killed us. When they would line up 3 wides to one side, we would counter with 1 CB, 1 safety over the top, and 1 LB cheating inside (not covering or even coming close). They absolutely ate us alive for 3 quarters with that set until we finally started bringing in an extra DB.
As for Purify, he is a very shifty back and made several tacklers miss him in the backfield. Add that to the fact that they were holding our DE's on EVERY play and you'll get some good rushing yardage.
Whoever said that Colorado dominated the line of scrimmage wasn't watching the game I was watching. Our kids were in the Colorado backfield all game long. Klatt was rolling out on every pass play from the very first snap and he had company on all of them. We had at least 1 or 2 guys on his heels at all times.
Contrast that with the time that Reggie got in the pocket. Sure he was rushed a few times, but overall he had time. Several times I thought he should have taken off with the ball, but he didn't.
Play calling was an issue. On 4th and inches we throw the ball? Huh? We just seemed out of rhythm altogether in the 1st half.