Right. They got 4.9 because they were a sneaky change of pace to Hill and Waddle. The current RB room on it's own is 1. frequently injured. 2. Not capable of consistently getting the yardage they got last year. Sure. They can get lightning in a bottle for a couple games but if we're in the scenario where Tua is down and suddenly the passing offense goes pop gun like it did last year, they are taking the current RB room out of the equation really fast and we're punting a fair amount.But to sit there and say....We got Mostert and Williams and their 4.9 YPC we are going to control this game rushing the ball.... IMO that 4.9 PC will shrink drastically. Big reason they were not dependable on short yardage plays.
However.... You have Cook in the backfield. You KNOW you have a back that can be utilized for that run game in a run first game plan who's 4.4 ypc won't suffer. He can carry the team and load.
What do you do if you're worried about your passing game falling apart if Tua gets injured again? You beef up the RB room. That means Cook.
I haven't spoken to Achane specifically as I think it would be unfair to really levy any expectations one way or another at a third round rookie.