He wasn't durable though was he? Isn't that why Di Luigi became a big part of the offense his last year, because Unga was injured? Then basically went back and forth with injury after his BYU days were over.
And I get your point... However he wasn't competing for playing time since those guys played a different position. Capable of carrying the ball, but they were FBs and started along side him, not in place of him.