See, I have a huge problem with the "But I don't want you to play the game that way" attitude. This is especially a problem when developers insist on their own unique control scheme in a familiar genre. When I move from one FPS to another, I want to be able to have familiar functions like crouch, jump, switch weapons, melee, aim, etc to all be on the same buttons.
Like recently, I've been rotating among Borderlands, BF:BC2, and CoD:WaW. None of the presets allow me to put the same basic functions on the same buttons across all games, and as a result, I make a lot of basic control errors when I switch from one game to the other. I don't think, "Wow, your vision for mapping crouch to R3 is so compelling!" I think, "Dammit, I just died again because I crouched when I meant to melee."