Bart Simpson: Hey Lisa, how was your day at Springfield Elementary School today? Did you play your saxophone in music lessons with Dewey Largo, Springfield Elementary School's music teacher?
Lisa Simpson: Why yes I did, Bart. Thank you for asking. How did you know?
Bart Simpson: Because that's what you do at the start of every episode, of course.
Ok, it's obvious I'm not going to get a job any time soon as a Simpson's script writer, and I'm not entirely convinced this is the best way to illustrate the point I want to make but it's the best I could come up with on short notice without quoting from a book.
What is wrong with this bit of horrid dialogue (other than the obvious)? Could it possibly be that Bart has included a lot of information that isn't necessary because Lisa is already very familiar with it? In other words, is Bart's dialogue completely unrealistic because really he'd say something more like, 'Hey Lis, how's school today? Did you get kicked out of sax class again?' (We're just pretending for a moment that Bart is a nice brother and he'd actually care how Lisa's day is.)
All the other information, the names, the places - the specifics - is not necessary. At least in the context of those two having a conversation. Lisa already knows what school Bart is talking about because she goes there. She knows who her music teacher is. She knows where her music teacher teaches. The only reason a writer would write a piece of dialogue with so much unnecessary information is because they are trying to inform the reader.
I'm here to say ... don't do that. Seriously. Don't. Unless you're trying to make your reader cringe.
Dialogue for the sake of imparting information to the reader, and not because it would be a natural conversation for the characters to have, is a great way to create stilted scenes. It doesn't feel real, and for good reason. It's a dialogue info-dump, and it's just as bad as the non-dialogue kind.
Do you notice the dialogue info-dump? Does it make you cringe? What other tips do you have for avoiding stilted dialogue?