Board Thread:Improvements and Issues/@comment-5355747-20130313062554/@comment-10587310-20130721085029

Aizen would have had to us Kyôka Suigetsu's power after the fight with White because Isshin went back to soul society and everyone still knew him. But when he left the second time and saved Masaki and lost all his power than Aizen could have used Kyôka Suigetsu's power.