They would have had to have left Arwen out completely and what is the problem with that again? ;)

Peter said in the interview that he expanded Arwen's role because the reality of making a hollywood blockbuster was there had to be a major love interest integral to the entire film, and there had to be a CHOICE between possibilities. *shrug* He is the film maker, so I guess he knows.. I still think that formulas like that.. devalue the audience in advance.. as if we wouldn't be interested in a quality story unless it followed a certain path.