We're not really a fastbreak team. When there's a break, it's usually Rondo by himself or sometimes Rondo and Ray or Rondo and Tony (who is now gone).
What's more, Kendrick Perkins was hardly an asset on the break. So I don't see how Shaq is going to really be any worse.
And he'll give a lot more offensively. Gone will be the days of Kendrick getting the ball down low (if he catches it in the first place), dribbling, and going up to get his shot blocked or altered.
And again, what's your solution here, have Luke Harangody or Semih Erden be the backup center? You do a lot of talking about youth and athleticism, but I don't know where you think we're getting that from.