User blog comment:Salubri/Aizen, Yamamoto and Wonderweiss/@comment-1712587-20100226150218

too true, esspecially given that a bankai alone hasn't been responsible for defeating a single Espada so far. 9 - no bankai, 8 - superhuman drug, 7 - needed splitting void to negate power, 6 - hollowfication, 5 - no bankai, 4 - uber hollow, 3 Aizen, 2 - own resureccion power, 1 Shikai.

most bankai have generally proved ineffective (kommamura and mayuri in particular) and as byakuya had shown both Renji and Ichigo just having one doesn't count for much unless you have a great deal of other skills and experience too..... or a psycho hollow inside you!!