I've been wondering if he's playing a little chess here. Getting the upcoming teams looking at tape where there is a steady rotation of personnel without any implications on play calling. Then, half way into the season, we see a shift where certain guys are playing more when they are ahead and running the ball, and other guys playing when they are passing it. Then, just when those substitutions start to mean something to the opposition, he switches it back to being completely unpredictable, putting the opposing defense off balance.
Probably reading too much into it...