User blog comment:Xilinoc/Ch. 577 - SWORD/@comment-11130627-20140416155018/@comment-1489595-20140419012357

Cool your jets, people. Lets not forget this theory has been around years longer then what we now know of the true nature of zanpakto, and more specifically, Yachiro (which was information dropped into your lap only a few chapters ago). At the time when you knew none of these facts it was a fan theory worth considering. I'm certainly not denying its now wrong. I just think it was a very feasible and cool way to explain such a weird relationship and character, at the time.

Aside from this I have to disagree about Yachiru's character. Her role up to that moment was strictly comedy sidekick and a board for Kenpachi to bounce character growth moments off of. Sticking 'Lieutenant' onto her did absolutely nothing to change this. I'm glad to see that she has gotten something besides 'irritating pest' on her resume. It was pretty thin on personality and competence otherwise.