User blog comment:Xilinoc/Ch. 665 - The Princess Dissection/@comment-24726378-20160310153033

So, why didn't he use this against Aizen? He could've restructured him while he was in his chrysalis phase, or heck, even before that! And how did they not have ANY data on his bankai? They've been spying on the gotei 13 this entire time and Urahara had to use his bankai during his captain's proficiency test!