The problem is that Pierce is having trouble not being a STAR, as defined by today's NBA. He seems to want to make every shot in the fourth quarter so he can get credit from his peers for being a STAR. If he would simply pass the ball to the open man he would eventually get the ball back or get an assist. Unfortunately, assists are not for STAR's, only points.
Pierce should be playing point forward ala Larry Bird.
On the other end, he should worry about rebounding first and let the point guard dribble the ball up the court.