User blog comment:Godisme/天地灰尽/@comment-443399-20120926152053/@comment-1641698-20120926184220

Imo... For your number two question, that will be a good explanation [Loyd Lloyd's Yourself speculation]. But I hope there's something more than that since I like Kubo's twisting of plots and characters. For number three, I think Sasakibe 'might' have used his bankai before, not for battle of course, but to train himself, like what Ichigo and everyone in Bleach does, leading to get the info about the bankai of those who had achieved it. I think they don't have info about Yamamoto's bankai because this was his first time to actually use it in front of SR and/or it might also be because Yamamoto didn't use his bankai at all before during the war. For Ichigo, he just popped 997-998 years after this war [Bleach timeline, I mean] so there's no info about him at all. On how they get info, that's a good question. They might also have something similar to the Shinigami Research & Development Institute but I doubt that.