BYU gets 95% or more 3 star recruits (or lower) in most recruiting years. 3 star recruits are basically "average" recruits. Some hit and some miss. BYU can take a lot more chances on overlooked recruits with the PWO program. If the PWO recruits come in and suck, then BYU can release them. However, the coaches have shown an eye for talent on the less heralded players and have found some real gems that can be developed.
I'll be pretty nervous if some of the depth walk on DBs get a lot of playing time. However, on basically everyone else they would be re-rated to 3 star or higher in retrospect.