I went and did some further reading on this. Apparently (based on a couple of articles I read) Castellanos had been operating the offense at high efficiency (qb rating in the 90s), but got injured and was out for a couple of games. After he returned, the offense went into the tank and his qb rating dropped to the high teens. He got benched and James (played while C was injured) replaced him. This guy apparently throws a very good long ball, and the result is that running lanes opened up and the offense got going again. It seems that James is gonna graduate this year, but BOB wanted to win now and Castellanos was not getting it done after his injury. Good for us....BC will be breaking in a new QB next year.