Often a documentary’s story really comes together in the edit. Think of it in terms of writing fiction. The “writing” of a documentary happens in the edit and that’s why often you see an Editor also getting a writing credit on the film. It expresses the amount of work that she/he has committed to the film’s final story. I know, and have heard, many Directors and Editors say their films were saved in the edit, or the filmmakers bought them a cut of a very different film and it’s now transformed.