two seasons, period. Of course he'll most likely end up with more. That's not the point.
To this very point, end of soph years, Unga had over 100 more.
BYU doesn't have a 1-2 punch at RB. Unga wasn't competing with anyone. And Jamaal is "more so" now. It doesn't matter what type of play it is. It's the fact that Jamaal has had nowhere near the number of carries as Unga.
You can also argue that Hall, Collie, Pitta, and others made it just as easy on Unga as Hill's running does on Jamaal.