Though we have heard often of stupid haste, skillfulness has never been associated with long delays.
One who is commonly referred to as a "dirty" fighter, is one who not only wins, but excels at winning with ease. Others would call this fighting smart.
His victories will bring him neither reputation for wisdom nor credit for courage.
The smart fighter seeks to put themselves beyond the possibility of defeat, and then wait for the opportunity of defeating the enemy.
To secure ourselves against defeat lies in our own hands, but the opportunity of defeating the enemy is provided by the enemy himself.
The consummate leader cultivates the moral law, and strictly adheres to method and discipline, thus is it in his power to control success.
If the enemy's position is secure, be prepared for him.
If his strength is superior, evade him.
If he is taking his ease, give him no rest.
If his forces are united, separate them.
Attack him where he is unprepared, appear where you are not expected.
If your opponent is of chloric temper, seek to irritate him.
Pretend to be weak, that he may grow arrogant.
If you know the enemy and know yourself, you need not fear the outcome of a hundred battles. If you know yourself but not your enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle.
Therefore the clever combatant seeks to impose his will on the enemy, but does not allow the enemy's will to imposed on him.
--"The Art of War" by Sun Tzu. (It's only 50 pages, every gamer should read it once)