Can the Rockets please play some defense?

Be patient my friend.

The coach can pull people out if they are not executing what was instructed to them before the game or during the timeout, can't they?

Isn't that what McHale has been doing to Lin? Managers do thing through people, so they are not totally irrelevant.

 

So who on our bench are the viable substitutions? You do realize that playing someone who is a slight upgrade on defense and a massive regression on offense is not a net win right?

At some point, you can't just have a revolving door of people sitting on the bench because they are all making mistakes. It's not one person making these mistakes, which would make it pretty damn easy to sit them wouldn't it? It's a multitude of guys and as was pointed out earlier, young teams don't play defense particularly well.