I use this tricks macro:
Code:
/cast [@mouseover,help,exists,nodead] Tricks of the Trade; [@focus,help,exists,nodead] Tricks of the trade; [@targettarget,help,exists,nodead] Tricks of the Trade
What it does is when you cast tricks, it first checks that the player your mouse cursor is over, if it is a friendly player that is alive, then casts tricks on them, then casts tricks on your focus target if your focus target is an alive, friendly player, then does a targettarget of your current target (usually the tank, but can end up tricksing a random dps or healer if they get targeted for something).
What I usually do is set a dps to focus, and mouseover tricks the tank on the pull.