Rule changes from 2014 were also reviewed, including the concussion rule and those that clamped down on cannonball and lifting tackles, and the referees' performance and the match review committee.
Meanwhile, former Kangaroo and Newcastle Knights five-eighth Matthew Johns believes reducing the amount of interchanges will help reduce wrestling in the tackle.
But Johns believed limiting the amount of interchanges from 10 to six would be an encouraging start.
Under Johns' model, once a player left the field he could not return.
He said there would be fewer in tackles as the game wore on and allow the "cream to rise to the top".
"When you fatigue the players, the game really opens up," he told Triple M Sydney's Grill Team.
"This will eliminate getting lots of players in tackles and will really go a long way to eliminating the wrestle out of the game."
- With AAP