An interesting editorial on MGS2's storyline

[A Black Falcon]

Games can't program themselves, so predetermined stories are really the only possible way to go... doing it any other way with any kind of story depth would be exceedingly hard and quite probably not worth the time. What you need (for such strories) is just to make the player feel like the predetermined choices aren't predetermined but that they are actually making it up as they go. :) But that too would be really hard... if you want a really focused story, the best way to do it is to make it predetermined. Anything else and it's a massive amount of work.