There's nothing in the laws of the game about an "unnatural position", it's all about if it was deliberate or not. Referees take massive liberties with the handball rule
OK, I was under the impression the refs were given briefs as how to interpret the laws, and that was one of them.
Graham Poll on the new interpretation. "So the question of intent is now, did the offender deliberately place his arms in an unnatural position to increase the chances of the ball hitting him?"