Note the
in her presence and when she
involves herself in a violent situation - meaning when she actually exerts her own will over something, rather than answering the prayers of those calling to her. These occurances would be incredibly rare, perhaps having never happened in actual Warcraft History, and there for Storytellers to use as a plot mechanic.
Still, the Night Warrior source is newer (and comes directly from Richard A. Knaak's War of the Ancients), thus this might be a retcon.
And yes, I'm very very happy about the Lore that Blizzard have decided to put up, at last!