These players are in the best shape of their lives. I would guess they all actually played more minutes per game in High School.I'd hope they can play 30 minutes a night. I have not noticed any sign of fatigue over the course of the season, even though some others disagree. Play to win the games and get them rest when you can without jeopardizing the outcome of the game.
I've always been an advocate of getting heavy usage out of the best players, so it is refreshing to see KD doing that now. The whole "depth" thing is right up there with our "high major size" that posters used to point to as a plus for the program. Both of which never got the program to where we want to be, so I am in favor of taking different approaches to try and get there.