I don't understand the preoccupation with the center position. In the Celtics system, the center is the position that is easiest to learn and adjust to. Its an easier job
And it also helps that whichever center is going to play, they are alongside 4 great players, and just play off of them. This is the reason why Erden, a Euro player who was a novice to US b-ball was able to play so well and be effective when on the floor
And people forget that this is how they won the title back in '08. With the focal point of the Big 3, all the other players were playing off of them. Whether it was PJ Brown, Powe, or Perk, they had a simple job to do. They were not the end all be all for our title hopes
Its not if Shaq is gonna be here or not. Any big would be helpful. Its just about how many bigs are in the rotation. 3 or 4 healthy bigs would be ideal, but a certain player there doesn't matter