Another small update.
I've beaten the Twin Val'kyr on 10man Heroic now, took me 3 attempts tonight.
Raid comp was 5.9k prot pally, 6.1k disc, six spriests (ranging from 5.3k to 5.8k), 5.3k boomkin, 5.4k resto shaman (missing some enchants/gems though).
I tried Anub'arak three times as well but only got him to 14%. In the last phase he summons two adds, freezes the tank and starts his AoE life attack. During which time there's a very high chance that my healers will die due to aggro'ing the mobs when the tank can't act. On the run where they didn't get aggro, my tank died from all the incoming damage because of the add's stacking debuff. I think if I was playing with two tanks, the fight would be pretty easy.
Hopefully in the next few weeks I'll have an extra prot pally to offtank for Anub Hc and for Gunship. Maybe I'll also gear a Hpal and make my shammy elemental like she usually is.
Little bit of advice for anybody who wants to box ToC 10 Heroic - instead of using DPS flasks, use the lesser flask of resistance. That 50 resistance per character eases up the amount of healing needed immensely. My Disc is ok to solo heal Twins with only one tank if using the flasks. Also helps if you're characters are alchemists since they gain an extra 16 resistance from the Mixology buff when using that flask ^_^