Originally posted by LordOfTheLightIndeed, and this is my point.
That is Obi Wan's initial aggressiveness working to his benefit.
Initially Kenobi's dark sided emotions did work to his benefit. If they had drastically hindered his overall powers, he wouldn't have been taxing Maul in that moment of anger/rage/frustration.
But as I mentioned: it was clear that said emotions were controlling Kenobi; he was not controlling them. They ultimately made him sloppy/careless, and Maul was able to capitalize on that.
And the Visual Dictionary excerpt I posted confirms that Kenobi wanted to tap into those dark sided emotions because they would allow him to defeat Maul. If said emotions were meant to hinder Kenobi's overall powers in that moment, he likely wouldn't have even considered giving into them(why would you willingly embrace something in a battle if you know it weakens you..?) Hence why it was worth mentioning here.