I am glad that they have included something on the cannonball tackle.
I was watching a game with a mate last year. This merkin is a died-in-the-wool Victorian. Not particularly interested in the AFL (he does go for Hawthorne, he just doesn't watch them until they're in the grand final). Anyway, he hates Sydney and the NRL. He says the game itself is actually pretty good, but the players are all f**kwits and it is extremely poorly administrated.
But I digress. We were watching a game, as I said, and some player ran the ball, hit two defenders and was pumping his legs making ground. Then the third man came in at his ankles and the ball carrier was brought down. My mate goes "Look at that shitmerkin! The bloke was pushing those two defenders back and then shitmerkin comes in like a dog and grabs his legs! Shitmerkin!!!"
I thought it was an interesting way for a neophyte (this bloke doesn't watch much NRL) to view this fairly standard defensive technique in first grade rugby league. I just accepted the cannonball as best practice tackling technique, but it must seriously detract from the game for a lot of viewers.
I certainly think the ruck is far too slow these days (especially Parra's) but trying to eliminate the wrestle places too much interpretation into the referee's hands. He should ideally be adjudicating rules, not interpreting them.
Anyway, third man tackling above the knee is fairly black and white so hopefully it works in practice and doesn't just lead to a swathe of controversial penalties.