Besides rebounding (which goes without saying nowadays and partly has to do with Doc Rivers' coaching style), if there's one thing that plagues this team and stops them from being unstoppable, it's their inability to have a consistent offense.
You can almost always count on this team now going through a couple of 5-7 minute stretches per game of just terrible offense and hardly any scoring.
And while I normally don't agree with Barkley on his Cs analysis, he's dead on right now. For the most part, the Celtics are still just kinda playing...going through the motions...no real energy. And it's almost like game 1 fueled it even more. Because for the most part, the Celtics really only played 1 quarter last game, the 4th, and was still able to win.
So I'm sure the thought has gone through their heads (especially Rondo) that if they can get a win against this team when only putting effort into one quarter, might as well do it again.