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AE Avoids broken?
This, like the mythical problem have already been addressed by Aelalik. They've been fixed internally and are waiting for the next hotfix.
It was an error with the druid AE blocker requiring a buckler while bladedance and other AE blockers do not. It's not intended to work as it is currently doing.
And as far as using it on Thet, because it blocks the AE on incoming and it saves the bards from having to respec for bladedance. Mostly, it's just an added precaution for raid members who might not yet be able to eat the AE.