No it comes down to Cally being to freakin stubborn to start freshman. It makes no sense either because Castille should be getting way more playing time. (There are many other examples)
I think Cally doesnt play these frosh because they dont know his 20 pound playbook front to back yet, and in practice this shows up, with Castille it is different because i think he actually knows what he is doing casuse our running game is so simple. The reason Castille isnt out there starting is because i would put money down that Callahan promised Lucky a the starting spot when he came here. Last year when B-Jax was tearing it up and became the starter Lucky told the coaches he was going to quit and go home, Cally begged him to stay and i would bet that he told him he was guarenteed atleast 50% of the snaps and that is why Jackson left for the NFL.
Also Castille has trouble holding onto the football sometimes but i would take that risk of a turnover with someone who runs as hard as he does.