Get rid of the worst and laziest defenders in the NRL and defense gets better - Averillo, Okunbur, Waddell, Alamoti, Perham, TPJ, Thompson, RFM, Casey, Pele, Sutton and last but not least Topine.
The biggest difference is the change in the centres. It's the hardest position to defend in you get found out if you don't have the smarts and technique - Averillo and Alamoti compared to Crighton and Xerri. If you are poor in the centres, it puts pressure on the whole team defensively and then the good players need to take the burden and either get worn out (King and Kiraz) or start making more errors than usual (Mahoney and Burton). This then means our attacking players are too tired to be effective at the other end in attack and we give away penalties and 6 agains and then we have to defend again - viscious cycle.
Throw in a fit Kikau and we have a leader who sets the standard on the field by action rather than virtue.
Credit to Gus, CC and the coaching staff who were able to identify this and did something about it.