BYU is tough to get into due to deman economics not because it is tough. They can take the highest score kids because there are a TON of LDS kids who's families value education and have great marks.
UVU is now a 4 year University and is the single highest enrolled student body in the state. It's because there are that many people who can't get into BYU. BYU just doen't have the room. Hence the Hawaii and Idaho campuses, etc.
They all want to go to BYU for a few reasons, none of which are due to ciriculum.
1) they want to be with other LDS people
2) they want to have a college experience in a great LDS environment
3) spouse hunt. Marry in the faith, there is no better mating grounds than at BYU
BYU is tough to get into due to competition (so many kids trying to get in). The actual classes are not more difficult. Not at all.
So, your theory of it being harder is just not true. Sorry. So the APR being low is not a good thing for Bronco or BYU ahtletics. By the way, Bronco does have a lot of kids on the grade bubble, every year. Also many don't finish school, like Max Hall, Harvey Unga, etc. Even though he was a senior. He majored in football really. Plus lots of them transfer. APR is hurt by them.