User blog comment:Nick D Wolfwood/Questions questions questions!! Kurosakigate.../@comment-1932702-20100624161952

Anyone have any opinions on Tensa Zangetsu? Why the hell is he so young (not that I mind, he looks good, like a Zangetsu-Hitsugaya mix)?!?

Spiritual genetics makes some sense, btw. And about this G13 theory, since NO ONE in the G13 recognizes the name 'Kurosaki', I'm beginning to wonder if Isshin was one of those 'previous' Substitute Shinigami that Ukitake mentioned. And Ukitake's a fairly old Captain, so Isshin might have been active way before any established time line we have.

I wonder if SS keeps records of Sub-Shinigami. If they did, then Byakuya would know the Kurosaki name. But since he doesn't, maybe the prev Sub-Shinigami (link to the Kurosakis??) were just not mentioned in SS history.