User blog comment:Xilinoc/Ch. 564 (Mask is too fabulous to live)/@comment-24113610-20140117070855/@comment-24113610-20140118200523

I know it's not unlikely but it's as you said... if the relationship between a Shinigami and his/her zanpakuto  is so intimate, then how did Renji not realize that Zabimaru was holding something back? He trained for 17 months after Aizen's defeat, got a great boost in power but never felt something was off with his Zanpakuto? What if he hadn't trained in the Royal Palace? Would he have never met his full potential?