Quote Andy Gilder="Andy Gilder"Defence is twenty percent structures, 80 percent desire and ability.'"
I think you're missing a few things there. There is a lot more that can be done in team organisation to make a team more effective.
Structure goes a lot further than people realise:
"Formation" - i.e. who's where in the line. (I expect to see more teams start playing their hooker wide by the way as we see more lightweight hookers and more additional props/2nd rows being used at loose)
Familiarity with that formation and knowing the habits and abilities of the players around you.
Alignment - inside/outside and where we do what in the line, and where we leave the space (the defensive line will have at least one less player than the attacking team)
Coverage - wingers or someone else scraping behind the line, who and when and why.
Changing any of the above according to field position - both horizontally and vertically.
Familiarity with opponents:
Individually - how they step, how they carry.
As a team - what moves are run, have we practiced against those moves?
Beyond that then, there's the individual and combination technique, especially in tackling. After all, when Warrington caught us on our right, it wasn't really any of the tactical stuff above, it was beating us in the carry in the middle and getting a quick PTB against a dented line, that didn't allow us to get much of the above into play prior to Warrington getting the ball into play again.
Most of the time, when a defence gets exposed, it's the play before you need to look at to understand why.