Like most of you, I spend more time than is strictly speaking "necessary" analyzing BYU sports. .
I have pondered on whether Bronco is the problem, or if he is "a" problem, whether he's "the" problem.
The hard thing to do is evaluate a baseline scenario. You have to answer the question-- "What would have happened to BYU football over the past 10 years with any other realistic candidate at the helm?"
The Bronco haters use Utah, Boise State, TCU, and similar programs as a baseline scenario. They assume that if we could only find the right coach, we could have done what those programs have done. They assume that KWhitt, for example (who is or at least was a realistic candidate) could have done at BYU what he did at Utah in 2008. They assume that if not, somebody like Gary Patterson (but LDS) or Chris Peterson (but LDS) is out there and that if we could only find him, we would be "back" to the early 80s (which is realistically the ONLY time we have ever been as good as Utah 2004-2008 or Boise 2007-2012-- and maybe not even then-- although we did win a National Championship we were only undefeated once).
But when I look at those baselines, I am not convinced. At least four things have happened since the 80s that have hurt BYU badly and make a big difference:
1) The schedules we play are much much tougher than the ones we played in the old WAC. They still aren't P5 schedules, but they are nothing like 80s BYU. People forget that LaVell, as good as he was, did it against horrible schedules. Horrible. Not mediocre, actually really really bad. And BYU generally lost to at least one of those horrible teams EVERY YEAR. We have upgraded our schedules without upgrading our talent. That is a tough combo. Even Chris Peterson couldn't do at Boise in a depleted MWC what he did all the time in the old WAC. Easy schedules are much easier to go undefeated with.
2) The rest of the world has discovered the Poly football player and the forward pass. In the 80s, we had two big things going for us. Personnel-wise, we were basically the only team in the two-A that heavily recruited Polys. It gave us a huge advantage. In the 80s, we would have gotten Manti Teo and Xavier Sua-Filo and Stanley Havili and Duece Lutui and Sealver Siliga and Star Lotululei and Haloti Ngata and on and on and on-- without much competition from anyone. Ask yourself how much better we could have been with just a few extra superstar poly players. Scheme-wise, we also had a huge advantage. We threw it all over, and teams didn't build their defenses to stop that. Their LBs were not capable of covering all our people, because they were built to stop the dive/off-tackle, not to cover in space. Today, that is an expected part of offensive football.
3) The honor code is far more strictly enforced. In the 80s, it is well-known that LaVell had all kinds of HC leeway which he was able to use to keep a guy like Jimmy Mac playing. Today, Bronco has some, but nothing like it seems LaVell had then. Today, there are tons of kids we would have recruited in the 80s (Porter Gustin, for example) without a second thought that today we won't give the time of day because of the Honor Code environment we live in now versus then.
4) I hate to say it, but the rise of Utah Football. I alluded to some poly players that the Utes got and we didn't above. But in general, the rise of the Utes has badly badly hurt BYU. In the eighties, for example, ALL the Kruger boys would have played for BYU. No question. You could go through the list of kids that have been great for the Utes and are from the state of Utah, and in the early 80s, we get 80-90% of those kids.
In light of all of the headwinds, it's actually kind of amazing that we are as good as we are. None of that excuses the fact that Bronco seemingly can't make good decisions on basic things like clock management, or the fact that we practice less than we are permitted to do, or some of the other boneheaded things I've seen from Bronco. The man is "a" problem at times. But he is a good coach.
And on balance, I think our decline is mostly due to macro issues that are far far from his control or really influence.