I'm not trying to argue with you and you do make some quality points but the truth of the matter is that Rak's starts and minutes at the 4, thru his first two season, have been by design while his starts and minutes at center have been out of necessity. Keep in mind that during that 6 game stretch that you mentioned, Rak and DC started at the 4 and 5 respectively for the first four of them. It was not until DC was sidelined that Rak began starting at center. But you are correct that in those remaining 2 games CJ and Grant both played the full 40 and Rak and Keita were not on the floor together. I cannot argue that Christmas spent more time on the court as a forward than he did as a center last season but I guarantee that if DC had been more serviceable he would have and he will next year. As for the "4 other forwards", everyone should take a moment and consider the past several years and JB's M.O. when it comes to freshman. Of course there have been exceptions but more times than not JB takes his time integrating the new class while the 2nd and 3rd+ year players, by and large, get the PT. Despite the expectations and talent of Roberson and BJ there's little reason to expect that either of them will get significant minutes. I believe Roberson will get a few (and I mean few) but I doubt BJ will do anything more than sniff the floor during non-con garbage time. I know you're not sold on Rak being a PF. To be honest neither am I. But that's where JB will continue to work him unless necessity dictates otherwise.
Just out of curiosity, if things were to unfold as you feel they will and Christmas starts at and plays center, presumably splitting time with BK, where do you see DC in this mix? Getting 3rd option minutes at center? Working minutes at the 4 with the belief that he's actually a better fit there than Rak? Or maybe mired at the end of the bench and lost in the shuffle? None of these are going to happen. Like it or not and for better or worse, barring injuries and/or suspensions, DC is going to play center and Rak will slide over.