Vigilance is a buff that a protection warrior can put on another member of her group or raid. The buffed person takes 3% less damage, and 10% of her threat goes to the tank who provided the buff.
The usual trick is to put Vigilance on one of the dps who is generating the most threat. So everyone benefits, they get to do some more damage before being threat capped, the tank gets to generate some extra threat, it’s all good. So I’m a threat thief, hurrah!
I find that I often tend to put Vigilance on the same person. I try to be aware of which fights are most threat-cautious for different classes, where the ranged guys cut loose vs where melee will be closer to my threat. But my usual Vigilance-buddy is one of our hunters. We have a deal worked out privately — he gets the Vigilance, and I get the misdirects.
It started slowly, like all good relationships. I noticed that his threat was high (and his damage even higher) and stuck Vigilance on him one night. The next week, he hugged me as we gathered together for Ulduar and whispered to me to ask if he could have Vigilance again. I said, ‘How about some misdirects? :P’ and a beautiful friendship was born.
See, most people don’t notice which buffs they’ve been laden with. To find someone who not only notices the Vigilance but appreciates it … well, it makes you feel kind of warm all over. I think he’s a keeper. But I admit it is an odd basis for a relationship.