You still haven't explained HOW 'interacting with a story' has any value. and what kind of value it is. My claim is, the only thing interactivity does is it invite audience participation, which is something people should be doing anyways. I don't see it as something inherent in story-games, although they try to enforce it. Also, Portal, seriously? You're not interacting with the story in any way, they don't even acknowledge any little things you might do. It's literally an audiolog playing while you solve puzzles.