How to make better decisions at the breakdown:
The first player should dive on the ball to protect it, with the second man coming in to protect the player on the floor. The defenders need to make the decision of whether to counter the ruck or leave it based on the body position of the attackers.
The third man coming in from the attack to protect the ball should 'clamp' onto the first attacker over the ball to secure them. The third man should come in and decide if they are going to pop the ball away or clean out the tackle based on the decisions of the first and second man.