DJViking is right on in his comments. In my view, Bone was/is a bonehead, when it comes to his substiutions and playing time.
I think your answer, though, DJ, is that Bone's decisions are based on playing and developing "his recruits," and his favorites. In this regards, he has and continues to make poor, flawed decisons. As you note, he blew the second half, as Morrison was just getting back into the groove, with 2 early baskets, and the Vikes had a 7 point lead (I think) at that point. He needs to show a little more faith and confidence in letting his best palyers play themselves back into it. Ian Ruder's blog today noted this well. Bone needs to "dance with the who brung ya's," and not look to pander to "his boys," and risk losing games, as he did.