Two things.
1) Ben Brown's run-up
2) The 'Take the extra time to set up for goal' only to pass the ball
They're both loopholes that shouldn't exist. The laws of the game should state that if you take the additional time to go back and kick, you should be committed to that kick. They should also state the maximum distance back from the mark a player can start their run up before it becomes play on.
What if we disallowed the short pass from a player taking the full 30 seconds by not paying the mark from the subsequent kick ie you take the 30 seconds than kick it short and the umpire just calls play on.