Random lagspikes ONLY in combat on a warrior, mainly on bosses?

Seriously. 3.3.5, and I cannot raid on my warrior who's primarily brought for Sunders. For some bizarre reason I go from ~200 MS, which is VERY doable, to.. around anywhere between 1000-5000 MS. I went up to 5500 today. That's utterly ridiculous, and it seems to happen nearly at random, but it spiked most of the time.

Add fights seem to be normal until someone pulls like A TON of things (such as the fleshreaper swarm at the bottom of Putricides' steps) or a boss-tag mob like Precious or Stinky. Or a boss in general.

Irritatingly, said lag disappears immediately once combat is over. For the record, I raid at ~4am ST. Literally right after resets. Usually because the raid forms and the server resets. I have had a similar thing in the past with some random addon's Swing timer (I can't remember the name to save my life, but I do know I don't have it anymore), which makes me assume it may be an addon.

Problem is.. only affects my warrior. Which is odd, because.. well, obvious is obvious, I use most if not all addons on nearly every character.

Addon list and non-combat MS. (It was iffy here.)

http://imgur.com/OfK7udr