User blog comment:Xilinoc/Ch. 587 - The Headless Star 6 (for real this time)/@comment-5693502-20140702183403/@comment-24153155-20140702213641

Hmmm...since he forges katanas, I think it would be cool if he is indeed able to put a little of his soul in just any zanpakuto and that he would be able to command any zanpakuto at any given time or space without him necessarily wielding the katana itself.