Board Thread:Versus Debates/@comment-29994364-20161028174112/@comment-3965545-20161119154851

He does not have lower reserves, he just knew he wanted to die while fighting Sasuke so in P2 he pretty much said fuck his own health, eyeballs, and chakra reserves. If this was a battle where they all thought "I'm going to kill these people even if it kills me" then Itachi would use the same amount of techs and chakra as he did vs Sasuke in P2. Prime Itachi btw is around the time he JOINED Akatsuki as there were no signs of him being sick at that time.