I've been using this method for a while, and it takes advantage of the AOE loot system(solo) or having a second player to loot/kill those mobs.
When you start the Rend Blackhand event, mobs will come to the balcony opposite Lord Victor Nefarius.
Mages, Warlocks, and DK's can AOE this mobs and get additional loot from them. (or the second player can kill and loot)
NOTE: You have to stand about 25 yds away if your direct-damage ability requires LOS. (only certain mobs LOS)
and for AOE ability, target edge.