Jeff White provided good analysis on Twitter( sorry too much of a luddite to post a link) .The ruck rules one is confusing, I’ve seen a few players really push the boundaries against TDK, Goldy being another, with things like that i get frustrated more with Tom and our coaches who dont know how to push the limits of what’s allowed. I thought it was disappointing that Tom just kept trying the same thing against Briggs even though he was getting smashed.
Briggs was setting up on the line adjacent the little circle, while TDK was starting at the back of the circle. This allowed Briggs to take about 3 steps forward, past the ball and blocks his run. TDK needed to set up directly opposite to get a run at the ball. It is complicated by where the umpire wants to approach from, but seems valid advice
Pretty sure they changed the rule to allow rucks to go past the ball to block rucks jumping which was a mistake and make for rucks grappling at CC's.