I'm a little puzzled by the terminology - I guess I took these for granted on Live. But basically these are part of the task system, except you get shared tasks that are almost always related to an instance (can't think of any that aren't tbh). This includes raids.
Since PEQ has GoD raids down I assume that they have used a workaround, or GoD uses a slightly different system than later expansions.
The main difference off the top of my head is that in later expansions group instances are part of the task system- they are considered "shared tasks". You can add new people to your task almost any time, although they tend to lock just before the last fight, to stop you task-adding (TA'ing) people at the last minute. That said you can still /taskadd people and they get credit even if they are in POK.
|