I read the manga. To tell you the truth, I think that the manga sux. I'm going to be watching the anime only from now on.
Alright, I can agree to Zaraki's lack of power to stand up to Aizen (somebody on a different thread showed the flaw in my reasoning), but Kenpachi isn't doing anything at all. You'd thing that after his phrase "I want to become stronger" he'd train or something, but instead he sits around in his office, wasting his awesomeness away.
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