I'm a playwright by trade, and in theater, writers have complete control over everything. Nobody can change a word without your permission. I've had a couple screenwriting experiences that weren't terrible, but they were typical, where executives came in and gave you sometimes good notes and sometimes horrible notes - but they wanted to change the movie that everybody had agreed to make. After a couple of times, it's like, "Why are we doing this?" The story is not going to turn out very good when 13 people are writing it together.