Everyone hates lag. Its even more important to us because to to the assist mechanic. Currently when the master tells the slaves to assist him you would think in a perfect world it would happen instantly since all five toons are located on the same computer. But the assist command goes to blizzard server then it jumps back to your toons clients. It's can sometimes take a relatively long time. So that's why you should drive with the tank so your tank can react quickly to adds or over zealous dps classes. At least in PVE instance scenarios. World quest content is usually pretty trivial. Zorbathegeek had a great isboxer FTL targeting guide to keep your toons focused on dpsing down mob in situations where the main may be tanking or off tanking different mobs at any given moment. Just google him and FTL targeting.