Sam wrote in with a question:
When did people start hating parentheticals so much? In older scripts I read like Chinatown and Godfather they're used in almost a quarter of all dialogue but now it seems people are of the opinion that you should never use them. Is this really the case with readers? Does the very site of a parenthetical immediately turn them off from a script even if used appropriately?
First, a word about these formatting rules because they tend to turn into the most heated threads on this site. I notice a lot of people who hate the idea of learning any formatting in screenwriting tend to phrase their grievances as an "all or nothing" sort of question. In other words, they might ask, "No sane person would really throw out my script just because I underlined and italicized every word, would they?"
No. But that would be a pretty big clue that the writer didn't know the first thing about how a script is supposed to look - or that they don't give a fuck about finding out. And let me tell you, writers like that often haven't figured out what makes a good story or how to tell a good story.
To put it another way - if I pass you on the street and you're unshaven, unbathed, wearing ratty clothes and seem to be moving erratically, I might not know for sure if you're homeless, but you're certainly wearing the uniform well.
So that's why guys like us make a big deal about this formatting stuff. And just so you don't think I'm beating up on Sam, these remarks aren't aimed so much at him as they are at the people who tend to get aggressive in the comments for articles like these.
Anyway - parentheticals. Beyond the reason stated above, there are a few other things to consider. If you're writing strong dialogue, you rarely will need to tell us how it's sad. The intent should fairly clear if you've done your job in establishing both the context and the character. As an example, let's say you've written a scene where a nervous rookie cop just pulls over a guy because his tail light is out. As soon as he comes up to the stopped car, the guy inside shoots at him, barely missing. The car takes off down the road as our hero goes after him. A chase ensues, during which our hero nearly hits several pedestrians and other cars, and nearly collides with his quarry before the fugitive rams a light pole and finds himself trapped in the car.
Our rookie cop gets out of his car, gun drawn. He runs over to his new prisoner and says, "Well, that was a lot of fun."
Do you really need a parenthetical to tell us that he's delivering the line sarcastically?
The other thing to remember is actors. Actors HATE being told how to deliver a line. If you go overboard with parentheticals not only are you constraining their interpretation, but you're sending a message that you think they are utter idiots if they can't figure out the tone for themselves (see the above example.)
Basically, if you're writing your dialogue properly you won't need more than five or six parentheticals in a screenplay. And if you're noticing that people are having trouble deciphering your tone, subtext or intent without those parentheticals, it might point to a larger problem in your writing (one that an experienced reader will probably notice even if there weren't 200 parentheticals tipping him off that the writer might be a newbie.)