[ashesatdusk]

I personally think theirs a bit too much of emphasis put on Kaien, I think he's an important figure in Rukia's life, but I don't think that means he's reincarnated, or still alive. The alive thing just seems especially ludicrous, because the death of Kaien wasn't just witnessed, they actually had his body etc.

Isshin is an interesting figure, he's very well knowledged about the SS, and his relationship with Urahara, and Ishida's father is interesting.... This is just a theory, but no one knows when Aizen's plots existed, but most of the people who seem to have knowledge of the plot hint that his plot has existed for several years. Their is a possibility he walked out of the SS around the same time the Viazards disassociated them selves with SS. Though to little information exists, the main reason is the Viazards are aware of Aizen's plot, and it seems like them have been even before the Shinigami had knowledge, and it seems to be hinted that Isshin had prior knowledge as well (as well as Urahara). It may be the discovery of Aizen's plans, may have caused groups of shinigami's to move. The one thing thats odd (other than the fact this is an anime/manga and the author can be absurd)... The presence of the Viazard means there are counting Ishhin, Yoruichi, Ichigo and Urahara 11 or 12 Captain Class Shingami in one area.