SOS before playing Auburn (that is when the committee had to make decision). Having a very weak schedule helps not only with a team able to win, but also to stay healthy.
The year that VT beat OSU, they were very young. After that win, they struggled because they were so beat up. That is what is especially hard about playing a hard schedule. This year all four finalists had Top 10 schedules. They were playing in a different world from UCF.