04 Nov 2007 at 17:49 - 80
Unienaule, UW and FoW have been around longer than you've probably been playing Guild Wars. I wouldn't put it past the average player to know how to do the areas (they've had long enough, and we'll ignore new players), join a group with someone who knows how to do the area, or know enough to use the IG search function to look up guides on wiki.
Besides, once a build is being widely used, as Ursan Blessing has, the average player usually picks up on it. Being harassed by PUGs usually does wonders to get most people using certain skills.
Now, you do have a valid argument that most groups probably can't FINISH UW, but you can't really blame it on them not KNOWING how it's supposed to be done, not that I fully blieve casual players are going to spend 2-3 hours clearing UW anyway.