Let me just preface this by saying that I am not trying to be antagonising. In case it comes across like that. Ok disclaimer done.
I've always thought that this is the area that QLD have the edge over NSW - both League and Union. It's very clichéd but the QLD pride that they speak of; the heart, the spirit etc. are very very real. I'm using some very sweeping generalisations here but I feel that it's something that QLDers tend to just "have". It's also something that NSW teams try to replicate.
It's certainly not something unique to QLD, God no. Plenty of other nations, provinces etc. have it. But when it comes to QLD v NSW battles I feel it plays a critical part. I honestly believe that it's something that the NSWmen sometimes just don't get. And this is often the difference.
EDIT: Lol! I just re-read my post and it does come across as a bunch of drunken nonsense but I am sober so I will probably get panned for this but I'm going to let my post run and see what happens.