Not all the way through yet, but these two paragraphs are really really good:

Quote Originally Posted by donkr article
When we have learned these strategies, we have defensive (e.g. unexploitable) strategies we can use both as the raiser out of position, and as the 3-bettor in position. Using these optimal strategies guarantees that better players can't exploit us. They will also win against players who play poorly, although they will not win the maximum (if we want to exploit opponent leaks maximally, we have to deviate from optimal play ourselves, and use strategies that target specific leaks in our opponent's non-optimal strategies).

Knowing optimal strategies also makes it easier to spot our opponents' mistakes (where we can define "mistake" as a deviation from optimal play). If we know what an opponent should have done if he had played optimally, we can conclude that he has a weakness in his game if he chooses to do something different. And we might be able to exploit these weaknesses and turn them into leaks for him.
It's elementary game theory, but it's tough to explain these concepts in two succinct paragraphs like that. It express like 4 crucial points all in one:

- Perfect (ie: unexploitable) strategy will never lose you money.

- Perfect strategy will win you money against any player who doesn't play perfect back (ie: everyone in the player pool).

- Understanding perfect strategy gives you a benchmark to understand player weaknesses (ie: any deviation from perfect play is a "weakness," so long as we define that as exploitable [though it might still be correct]).

- Understanding perfect strategy gives you a benchmark to understand what deviations you yourself should make to exploit those weaknesses (though it doesn't give you the answer to whether you should bluff more/less or bet for value more/less or play more/less aggressively, etc, once you determine that answer, it gives you the answer to "more or less than what?").