that last screeny, one died early, or did you put on on healing/tanking ?
not sure have understood what you talking about

my tank heal always himself , when i heal him and when i heal any other dps (my personal choice because he continue getting damaged^^). And one dps heal him too when i want healing other dps. it s a bit expensive in terms of tank mana but really useful to avoid tank healing blackouts.
a config like this:
Macro1 all heal himself(useful when get hitted by aoe) ---- Macro2 all on tank (tank included) (considering latency issues) ----m3 m4 m5 m6 one for each dps (3on that dps and at same time tank and 1 dps on tank).
Anub'arak is almost frustrating, avoid pounce(died often here, bad positioning, sometimes boss runs on border and i cant avoid it), move and dispel poison(it stacks :/), get aggro from adds. a lot of things to do.
King in UP is just 1 thing : remember to use shield when he summon lighting spheres, and become a simply tank and spank with some dispel.