Over a third of his yards came in the New Mexico State game (155 yards of his 423 for the season). If we remove the NMSU game, his season average yards per carry drops from 5.6 to 4.7, which is essentially the same as Tyson Williams, but against far inferior competition. I would be surprised if Williams wasn't named the starting RB barring injury. Katoa may have an edge at the moment due to playbook familiarity, but if Williams works hard I expect him to be RB1 by the end of fall camp.
Katoa needs to prove he can stay healthy first and foremost. He got 19 carries against NMSU before suffering a season-ending injury, 15 against Hawaii, 10 against McNeese State, 8 against Washington, Utah State, and Arizona each. Only a couple of carries in the other games. Then he needs to prove he can play well against good competition. His rushing average was only 3.0 against Washington and 3.4 against Utah State. None of the other teams BYU played where he saw significant carries had good defenses.