The issue was that defenders had started going to block the ball with their arms out, knowing that of they didn't block it with their body it would hit their arm and couldn't be handball. They then changed the rules to try and stop this, which is how we ended up with the farce we have now. The easiest thing to do is just have a blanket rule that if it hits the hand it's a free kick or penalty no matter what. In field hockey if it hits your leg it's a free hit whether you mean it or not. This would stop any debate.