personal experience is that Bronco would use the PWO for kids with high academics that also had some football skills. The purpose being that this PWO's academics could counteract the scholly player they did pull strings for with much lower academics. We were told directly that there was no help for admission, but there was help for class scheduling and the academic center.
Team GPA is an important metric for football (at least it was for Bronco), and there may even be a financial incentive tied to it for the HC. Bronco had pretty tight reins on the team academic performance, and when Kalani came in and relaxed those requirements the team GPA hit a historic low. Bronco did things for a reason, Kalani learned that the hard way directly from the admin.
As a walk on, preferred or not, if you didn't have a 3.0 each semester you were not allowed on the team. That same rule did not apply to scholarshipped players. I can testify that under Bronco even a 2.95 wouldn't cut it, you'll sit that semester. Even if you took very hard classes as a freshman and weren't told about this rule until AFTER the hammer is dropped on you..... and even if other position coaches you played for asked Bronco directly to not enforce this unknown rule.
This leads me to believe that Bronco saw the PWO value in many cases ONLY to be their academic contribution, otherwise why would a HC not want his player practicing football as much a possible?