Looking at season stats: Penrith are surprisingly high on the negatives - errors, ineffective tackles, penalties conceded and handling errors. Souths aren't fantastic either. Both teams, however, are at the top of the table for run meters, post contact meters and kick return meters. Both teams have players who are nailed into their positions. The best coaches don't chop and change; they perfect individual, specialist skills.
To me the stats show that territory - game management - is super important.
Both of the grand finalists have brilliant halves and spines. They both play very territorial, tactical games. Penrith specialise in stopping the opposition from getting near their line and, when it's under threat, their line defence really steps up. Souths specialise in engaging the line and try assists.
It's not as simple as defence or attack, star players or even discipline.
It's mainly about game control and being really well-drilled and cohesive as a team.