I've always been a firm believer in redshirting, especially with Boise State because of the complexity of the schemes. From what I've read online and according to the RB coach, Ajayi will likely start the season as No. 3 on the depth chart.
Martin and Harper are more than capable of handling a season's load of carries. And Drew Wright has shown glimpses of potential when given the opportunity. Former OBNUG-crush Malcolm Johnson has returned to the program, and Raphiel Lambert is also listed. With four running backs already ahead of him, why should we waste a year now, instead of saving him for when he will be the featured back? If there are injuries (ahem, Harper), then we would burn the redshirt with little doubt. But unless this is the case, I don't see a need for him to waste an eligible year with minimal carries.
Ajayi is definitely the future of the backfield. I just think we should stay patient, let him understand the system better, get bigger and have four years of amazing Ajayiness, not three.