We discussed this on the old TWC. There are two ways to do it: Voice or Text.
Voice - ruins the whole damn thing. Everyone has how the characters sound worked out in their head, and being forced into hearing "This is it, now what you thought, but this" is terrible. Like when you really like a book, then they make a movie and the characters aren't anything like you got used to them being.
Text - This requires everybody to read at the exact same speed as the writer. If they read slower, they miss bits of text, and if they read faster, they sit there looking at the panel for a little while before getting the next part of the story.
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