Players in video games don't use realistic physics, these are only used on objects the player can interact with. The reason is simple: players aren't inanimated objects, but animals, and animals have legs which are continuously used to counteract the physic pushes the animal receives. Using "correct" physics on an player simply produces a wrong feeling. The only times when the player can make use of true physics are a/When it's dead or b/When it's being pushed so hard that is sent to fly by an external force so he has no control. And even on case b, physics are still not real, cause the player must keep it's visual reference, so it's kept with his head up, something that wouldn't happen with correct physics. This applies the same to old idTech3 as to any modern game using the fanciest physics engine. Players are always a exception.
