I'd use Cassell if Rondo or House broke his leg, but other than that, I think that experiment should be considered over. Maybe give him some minutes in the first half just to see if he can do anything, but really, House deserves the playing time. Sure Cassell might be able to bring the ball up better, but then he'll pound it until there are four seconds left on the clock and take a fadeaway jumper, which is ok if they all go in, but lately none of them have been.
How's this for a simple idea- play Rondo 45 minutes, and bench Ray Allen. I'm serious- something is drastically wrong either with Ray's head or with his body, and "wishin and hoping" he turns it around doesn't seem to be working. Why not use Pierce, House, and Posey at the two.
And Budweiser- I couldn't disagree any more about Rondo. He does so many good things out there, I really think you're nitpicking a little about the "ball movement" thing. I see the same thing sometimes too, he's out there dribbling and nothing is happening, but is it just on him, or is there a play breaking down, or no one is open, maybe just good defense? Not sure, but I'll take my chances with him running the show.