Multi-tank busters should apply to the main tank in an alliance instead of a DPS

[Ultimatecalibur]

if a tank in an alliance dies the buster should apply a 2nd time to whoever is MT, because they have the utility to survive a 2nd buster, it's been horrible playing the nier raids as a DPS and getting the buster when your party's tank dies

No. If things worked like that you would justify 1 or 2 tank/6 Healer/16 or 17 dps compositions and party targeting mechanics prevent other party's from being punished for another party messing up.

I'll second that this is completely rubbish, I've often been an OT in alliance without stance and still taken the intended simultaneous tankbuster while a couple DPS were ahead of me on the aggro list.

Different alliance fights have different targeting rules for their tankbusters, healerbusters and dpsbusters. Some fights have single target busters that target the person with the highest enmity while others have mutlitarget busters that prioritize the tank in each party. You can usually tell the difference based on how the fight is set up.