Apparently this is a common problem, so I'll fill you in: in English, the pronoun "I" is always capitalized, even when not the first word of the sentence.
I have always done Sarth3D as unholy, even post nerf to BS AMZ etc.. I recently re-gemmed and lost a decent chunk of HP so i usually sit on 29-30k with 3 drakes (including Commanding shout.)
With the BS glyph and popping dodge or parry trinket, the 6 charges usually last 2-3 breaths, and i survive each one with only the BS mitigation. AMZ still prevents a death. Altho, i do cut it close on the majority of breaths, we never wipe to my death. I have a Disc priest on me which helps, but since the BS glyph and the CD change on AMS, i rarely have the need for Pain Suppression.
I do want to try a Blood Spec in the future for a Naxx, as i am always looking for something different. but i dont think i will try it on Sarth...