This exploit requires dual spec. one spec where the mage is speced into the focus magic talent, the other spec not.
For instance in PvE I spec 0/53/18
For PvP I spec 20/0/51
So, this is the exploit, during raids switch your spec to where you have focus magic talented, put the buff on a player in your raid, then spec back to your main PvE spec. Focus Magic still procs and gives you the buff.
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