Honestly in all I've watched footy, you can't run around your teammate if they are engaging the defense.. Isn't that the definition of shepard? Sure you can pass but how was Hodges allowed to run behind his decoy? Shouldn't Mini's try in the 04 GF been awarded then?
From the 2011 NRL Rule book:
Obstruction:
a) It is the responsibility of the decoy runner/s not to interfere with the defending team.
b) The ball runner cannot run behind his own team and gain an advantage.
c) A sweep player may receive the ball on the inside of a block runner as long as there is depth on the pass to him. It there is no depth he needs to receive the ball on the outside of the block runner.
d)
Defensive decisions that commit defenders to decoy runners will not be considered obstruction.
e) Attacking players who loiter next to the play the ball can be interpreted as obstructing the defending team.
f) In the process of scoring a try an attacking player dives through or into the legs of the player who has played the ball a penalty will be awarded to the defending team. This action will be interpreted as obstruction.
g)
If in the opinion of the referee/video referee the play had no effect on the scoring of the try the try will be awarded.
The two passages in bold are key to this decision. Farah was not impeded by Hannant, and then consequently never made an effort to get to Hodges. Instead he threw his arms in the air and appealed for the penalty. Scott stepped towards Hannant and then committed to Hodges, but held off him and watched Hodges step around him. Carney was simply fended away by Hodges.
Farah gave up the chase on Hodges, and was never going to get to him anyway. Scott and Carney both had opportunities to tackle Hodges, but Scott held off him, and Carney was swatted away. Hodges going behind the path of the decoy runner had no impact on the try, as the same defenders he would have been going up against had there been no decoy runner were still there and able to tackle him. And they both let him through.
Try.