I found this article in Script Magazine. I thought it said some great things about not using flashbacks in screenplays.
Used properly, flashbacks can be a great asset to a screenplay. So, why am I suggesting that you avoid including them in your script? Because, if you’re like the vast majority of aspiring screenwriters, you don’t use them correctly. Here are two common examples of the wrong way to use flashbacks:
- For exposition, as in: “Oops! I forgot to tell you this important information about the story or my character’s background, so I think I’ll pick up some of this stuff along the way, using flashbacks.” Quite simply, this results from lack of adequate planning before writing the script.
- To create audience sympathy for your main character, especially in a drama. For example, showing us in flashback that he was beaten up by the school bullies back when he was a kid. We don’t need to see this.
Remember, it’s always best to start your story as “late” as possible in the trajectory of your main character’s life — right before he undergoes a major dramatic change and he’s confronted with a crisis that is the central dilemma of the story. Start in the present, and stay there.
Read the whole article here: http://www.scriptmag.com/2011/08/01/breaking-in-its-high-noon-for-flashbacks/