User blog comment:Xilinoc/Ch. 575 - THE KILLERS HIGH/@comment-493809-20140402153858

Kenpachi Zaraki was once said to have a constant release-type Zanpakuto, just like Ichigo's (and being the only other known example).

They probably both had constant release-types due to the fact that they didn't actually have Zanpakuto at all, but rather generated their blades through their own power.

As such, my theory is thus: Kenpachi also has Quincy powers, and unknowingly holds the same power as Haschwalth(sp?) - the "B" (most likely Balance, due to the imagery and phrasing of Haschwalth).

Which would mean that, while he could pull out Bankai, I think it's just as likely he uses some Quincy techniques and wrecks the Sternritter's invasion.

Highly implausible, I know, but a man can dream, can't he?