A big part of any coaches rotation decisions are determined by what they see in shootarounds and in practices between games, which we as fans never get to see. At the end of the regular season, Doc had his 8-man playoff rotation set, and it was pretty [dang]ed good. Hell, even the 10-man rotation ain't too shabby.
I think it's obvious to me that everyone is hurting in some way or the other, and Doc is seeing it in the practices and shoot-arounds, so he is having to experiment with some new line-ups on the fly.