Going to try to keep this short for once--
Came across this in a couple submissions. You know how you sometimes use action instead of "he said"? You know:
Tammy rose. "You're a fool, Tommy. Bear Stearns is NOT a great investment!"
That's a good way to help the reader keep track of who's saying what, without repeating "she said" ad nauseum (or that immortal pre-war quote tag-- "Wow!" he ejaculated), and it injects some movement into what might be a static scene.
However, the action isn't JUST a quote tag. The astute reader is subconsciously keeping track, and if you have Tammy rising, and then standing up, and then pulling herself to her feet, well, the reader's going to wonder if the chair is following her around and repeatedly implanting itself on her bottom.
So block your action. Yeah, just like they do in the theatre. Make sure if there's an opening action, there's a closing one too. If she rises, she either sits down again or starts moving. If he pulls his cell phone out of his pocket, he should either answer it, make a call, or pocket it again.
In fact, it wouldn't hurt-- well, yeah, it'll probably hurt :)-- to actually write these "internal actions" down separately and make sure they make sense.
Says Alicia, who once had a cowboy hero remove his hat three times without putting it back on. Well, maybe he was a hydra-headed cowboy!!