It's about the characters, it's about the film, it's about the process of making stunning visuals and a huge, epic movie. It doesn't matter if my head was covered in a black plastic bag and I was bouncing around in a space hopper: That's the villain of Chris Nolan's 'Batman!'
As long as a film stays unmade, the book is entirely yours, it belongs to the writer. As soon as you make it into a film, suddenly more people see it than have ever read the book.
It's much easier to cheat than it is to be loyal. Everyone goes through down times. You just don't put yourself in those situations, you know?