If you have no relic. And up against a Macro'ed well played Relic +1 Bard they will almost always take your aggro if you're not doing Emnity combo off the bat. Even more so if they do triple target Dot that AoE threat is impossible to keep up due to River of Blood. But as far as AK goes if you're doing your rotation well and the Bard is taking aggo off you he should be able to handle it himself fine, no point stressing over it and let your other 2 mobs go rampant.

Overpower is only good to stick mobs so healer don't get aggro off the bat.

As a Paladin/Warrior/Bard player myself I know full well on the receiving and giving perspective.