I'll start by saying I am not a fan of Eddie House playing point guard and I like the Cassell signing a lot. I agree with Teddy - without Sam Cassell, we don't win Game 1 and I don't know if we have the 2nd quarter run in Game 2 that turned the game around. For that reason alone, I think it's ridiculous to say "he's earned a spot on the bench waving a white towel." He's played more of a role in winning games in this series than Ray Allen (who was a non-factor in Game 1 and roughly equal to Sam in Game 2) or Rajon Rondo (who I love but has essentially been a non-factor throughout this series, until, of course, Monday, when he started playing well and Doc decided to pull him for the first half of the fourth quarter). There is a need for Sam Cassell.
That said, I do agree that when his shot does not appear to be on, like it wasn't on Monday, we should switch it up and go with House. I don't think he'd hurt us as much in this series with his ballhandling weakness as he would against, say, Detroit. We should have done that in the 3rd quarter of Game 4, given House a shot with a few minutes left in the quarter to give Rondo a spell. If House looked efficient, you give him another minute or two to start the fourth and bring Rondo back. It didn't seem like a difficult read of the game.
And maybe Sam just has trouble on the road and we don't rely on him in those games. That doesn't mean he should be benched entirely, since he's been important for us in our wins.
I don't understand what Doc is doing with substituation patterns generally, this is just one of the examples. Our players are inconsistent, our coach is in over his head, we need the home court to carry us tonight.