I'll post something real later, but I just felt like calling attention to this:
AMS Nerf: Ambiguous Wording (WoW Forums)
(Summary: AMS will absorb a maximum of 50% of your HP in damage, so if you have 60k HP, and you're hit for 100k, AMS will absorb 30k, you'll take 70k, and you'll still die.
100% Reduction: Never a Good Idea
Off to work!