I would love to see the evidence that RAAFies going to ASA have more sep breakdowns! That is drawing a pretty long bow.
Both organisations go through phases of being the media whipping boy. I havent seen much difference between a good controller ASA trained and a good controller RAAF trained. However, a crap controller is still crap regardless of their training. The main difference is that ASA has a better operating system. Lets face facts, if it wasnt for TCAS and STCAs there would have been some airframe losses. The RAAF has a system that Moses bought down from the mount.
So putting the pissing contest aside, controllers in both organisations do what they do (with different imperatives) quite well. And everyone from the top down is trying to do it better.