Actually it's quite easy to coordinate. Have one person on your team harass healer while rest of team goes for dps.

Works in most pugs, not normally in ranked... It all depends on the other team... Also leading with the same strategy each round can alert them to what your plan is... Sometimes a focus switch will catch them off guard

I do like the harass the healer option, as long as you also switch back to DPS while the healer is Cc''d or stunned... Also watch for Sorc bubbles and switch... If you see a Sorc drop an AOE heal... Knock or pull the focused player out of the healing area... Separating the healer from the group and/or away for the tank helps too... Especially if they are an epic healer... If the tank guards the focused player and the healer can "free" heal with no pressure it is extremely hard to kill the focused player

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