Scott at 2013-02-25 19:18:08:
That's a terrific point, Debbie. I've heard some kvetching about Shawshank whereby someone didn't buy into the movie because the prisoners didn't seem 'real,' as compared to the gritty realism of the HBO series "Oz" for example. My response to that has always been that Shawshank is precisely your point: It's a fable. It's a plausible, credible story universe, has just enough edge to it -- The Sisters, the chief guard Hadley, Warden Nortion -- to make a threatening, antagonistic environment, but at its core it's about hope vs. institutionalization, living vs. dying.
So to your point, perhaps one of the reasons the V.O. narration works as well as it does is it fits the nature of the story universe. Once Andy leaves the Old World and crosses the threshold into Shawshank prison, that's when Red's V.O. commences, and at that point, the fable kicks into gear.
Therefore maybe another guideline: Voice-over narration must fit the specific nature of the story. This bleeds over into another discussion: Genre + Style = Narrative Voice. In this case, the V.O. becomes a critical component of the story's Narrative Voice.
You know, I'm glad we're doing this series and the one on flashbacks. Makes me think we should do it with montage, breaking the 4th wall, and other devices. Again just to get us into a thoughtful place re them so we if we decide we NEED to use them, we use them WELL.