So, I worked my few connections (which are not the most reliable, a lot of BYU people think they know stuff but they mostly just talk a lot) and this is what I found out - Pope is viewed as a really good coach that's matched up really well with the BYU program. He gets BYU, and is able to talk about how things some athletes view as negatives (fear of the honor code, the high religious population) are great positives to players with a certain focus strictly on becoming better basketball players. It also sounds like he and Haarms connected as skilled big men and just hit it off. Combine that with the thought that Pope knows how to put a big in position to succeed, and add in that there's room for a guy to step in and be a big contributor after a lot of talent finished up, and there is a clear path for Haarms to be heavily featured. This was simply a case of a great match between player, program and coach and Pope was able to represent that in a way that Haarms was most comfortable with.
BYU will always be able to pull a certain amount of talent from athletes already affiliated with the church, and there's growing optimism that Pope is building the credibility to expand the recruiting pool