User blog comment:Xilinoc/Ch. 664 - The Gift/@comment-11446176-20160226034831/@comment-3423279-20160226064356

Kisuke bound Aizen during their fight, so I would presume it is canon.

More to the point however, Askin is a Quincy, and a much weaker version of Uryu managed to basically take Soul Society apart to power himself when fighting Mayuri.

I guess that binding a guy who can absorb spirit particles and energy with.. more spirit energy... isn't that good of an idea, or at the very least won't work for long.