User blog comment:Xilinoc/Ch. 684 - The Blade/@comment-24769684-20160728121813/@comment-5398287-20160728123711

"Aizen reveals to Yhwach that he tricked him with Kyoka Suigetsu. First, how does that work still?? There's absolutely no reasoning behind why it works except for, well, it does. And when did Aizen show Yhwach Kyoka Suigetsu? You're telling me Chair-sama's one weakness, besides blasts of holy omnipotent power, is Zanpakuto regeneration and usage? Gee, that totally makes sense. And if Aizen could hypnotize Yhwach that quickly, as I say once again, why didn't he do it to Ichigo in their fight?? Sure, it just so HAPPENS that sparing Ichigo then allowed this keikaku to work now, but who knows if this would have even happened if Aizen won in the first place?"

It's known as "Complete Hypnosis" for a reason, and once again, there was never anything up until this point demonstrating that Yhwach could overcome illusions and such. OP powers interacting with each other. As for Ichigo, ARROGANCE - which Aizen has clearly learned not to let influence him in the 2 years since.

"OK, so first let's tackle Ichigo's Bankai. ITS ONE FREAKING POWER WAS TO RESTORE ICHIGO'S OLD SWORD? DOES THAT NOT DEFEAT THE ENTIRE PURPOSE OF ICHIGO REINVENTING HIS SWORD TO ENCOMPASS HIS FULL ABILITIES? And if Ichigo's got his old Shikai back thanks to his Bankai, does that mean his Shikai is now Bankai? Well, at least his sword skills seem to have improved a bit. And it's not like he'll ever need to tackle that particular issue since Ichigo will never use Bankai in the story again ._."

Nope - this was the result of Ichigo losing his Hollow and Quincy powers, which caused his sword to revert to a much older, but still usable, form. With all his powers intact, it probably did something completely different.