Shaq is ONE OF them most dominant players in the NBA. The most dominant in baseketball really is up to each person to decide. But to not give him his props for his ability to "over power everyone with his strength and dunk it and get fouls" is the sign that one denies his ability, because that ability gets him 27.2 PPG(25.8 PPG) and 10.7 RPG(12.6 RPG) (Parenthesis is his playoff numbers). The only Center in the NBA that can compare to that is Tim Duncan(25.5/27.6 PPG, 12.7/14.4 RPG).
Plus Shaq can still block shots so he is valuable on the defensive end also(the presence alone makes people hesitate coming right at the hoop).
The object of basketball is to score and to prevent the other team from scoring. That means actually scoring, blocking shots, rebounding, and getting assists(not the main job of a center though). Doesn't matter if it is done by hitting shots from beyond the 3-point mark, or getting them only in the paint and free throw line. Their aren't extra points for doing it in different fashions unless you shoot beyond the arc, and Divac can't do that himself.
That said, Shaq, if he wasn't as huge as he is, would be merely an average center. But that is like saying, if Bryant didn't have that touch he has to his shots, he would merely be average.