User blog comment:Godisme/Everything But The Rain/@comment-28861328-20130307061758

That sidenote kinda throws a kink in the quote by your favorite character, doesn't it? "You are the son of a Human and a..." then Isshin appears clad in Shinigami gear.

Not to mention, never once in the manga, nor anime, was it ever said Isshin got a gigai, that he lost his powers, nothing. They're all assumptions. Prove to me he lost his powers. Anyone? That he had a gigai? Hm? Thought so. Ichigo is a Shinigami. Thus, why he had latent Shinigami powers.