TCU was #73 as an example. Michigan #79, Stanford #86, LSU #87, Michigan St. #97, Washington #99, Florida # 104, Utah #108, Auburn #108.
BCS National Ranking:
Stanford #7
Florida #9
LSU #14
Michigan #24
BYU's offense was exactly average. #60 out of 120 schools. Lot of good names worse, offensively, than BYU. Yet many finished with better records and even nationally ranked. And every ranked team (and very likely every team on that list), had a tougher schedule than BYU according to SOS rankings and common sense.
BYU also finished ahead of every one of those programs in total defense. Yet, BYU likely would have been beat by every team on that list. Utah is potentially the worst team on that list and they beat BYU.
What you needed was not an AVERAGE offense. What you needed was a better than average, to really good offense to have a special year.
What you needed was better coaching. It seems help is on it's way on that front.
Also, maybe, just maybe, BYU's defense wasn't as good as their "statistical" ranking (Defensive rankings are not done on a SOS basis, just on pure game/total stats. How easy or hard the competition was, is not factored in). (i.e. Notre Dame rarely performed well no offense this past year, ranking #80 in scoring offense. They averaged 189 rushing yards per game, yet BYU gave up 270 rushing yards to ND - yet BYU is ranked #2 in rushing defense, statistically).
Every team on the list above, had a lower ranked defense than BYU, as well as a lower ranked offense. Yet, they would have likely beaten BYU in a game. Many were nationally ranked and all had more challenging schedules. Rankings based no statistics does not tell the whole story.
Now, that said. BYU did have a very good defense this past year.