I kind of go back and forth on this. Obviously you want more minutes out of your best player, and by not allowing him to play 15 in the first half due to foul trouble that's obviously not going to happen. But the other side of it is the other team is going to attack the player in foul trouble by either going at him to draw a foul, or so that he has to back off and give them an easier lane to the basket. Not sure which is more costly.