you hear so much of that in the media, that it is in your mind when you don't play BYU every year. So his impression is the same as many fans on that side of the country. Coach O is also TIC about a lot of things. He has studied the roster and knows BYU is not fielding a team of 26 year old players, just playing off the usual banter.
Age aside, BYU fields a more mature team than probably anyone in College football, meaning better disciplined and hopefully better prepared.