The PvE / PvP split has long been argued, and rightly so. However, there must be some fundamental dynamic to WoW's programming that prevents this. I can't see them NOT making an easy fix like this otherwise.

Personally, I've always thought that the easiest way to deal with this difference is to make PvE more PvP-like. Make it so that bosses can be snared or CC'd. Make it so that one set of gear is all you ever need (instead of one for fighting computer-controlled mobs and another for fighting players). Make more room for utility in the PvE game and perhaps you will get rid of players that are arguing that their DPS has been nerfed due to something in which they do not participate (PvP).

The PvE game should be more about fun and less about DPS and ePeen comparisons. If bosses and other mobs weren't all immune to CC, would that lead to exploitation? Probably, but then you (Blizzard) are the developers, figure out a way to throw a curveball that allows for the utility you've given the players and still provides a challenge.

Of course, arguing about all of this is pointless. Blizzard is perfectly happy to sit on their enormous profit margins made from WoW and not invest any more of that than absolutely necessary into making the game better. We get the same rehash, over and over and over again. And even their story-lines (once the reason I played WoW) have gotten incredibly weak ... so I don't expect the DK (or any class, for that matter) situation getting any better any time soon.