User blog comment:TVthePunisher/407 - Decide 9 (TV's Liking the Chapter)/@comment-1752519-20100614140652

that is speculation... but more likely... i think aizen was above tessai even normal, altough by very little margen... but whe cant really confirm whos right so whe should not argue about that

evolving form: he was stronger than isshin, speculatively he PROBABLY was 3 times stronger than a captain, no character in the series shown could have beat him in that form without help

crysalis form: he was so strong that he could handle 3 characters well above captain level (yorouichi beats soi fon without a zanpakuto and without battle rhytm, urahara proved to be stronger than kyoraku, hes probably twice as strong as the ordinary captains considering this and isshin... well he must be around yamamotos level from what he showed.... if not even slightly above) reiatsu so high that being too far under him cant even sense or measure it (my speculation... around 4 times a captain)

fully evolved form: so strong that he seems to be able to destroy anything, nobody can measure up to him (speculatively: 5 times or more above captain level ... like i said power levels are just my speculations, but each time he transformed the power increase where notorious)