User blog comment:Lia Schiffer/409: Deicide 11/@comment-2004597-20100624204720

Maybe that is Old Man Zangetsu in another form, it's just Ichigo's Bankai, I'm sure it would be OMZ if Ichi went in there in Shikai. His Zanpakuto is still Zangetsu, just now that it's in Bankai, it's Tensa Zangetsu. So, if that's just another form of his Zanpakuto, then maybe TZ is just another spirit form of OMZ.