If a boss hits you for 25% of your HP on every attack, I'm gonna consider a good mixture of avoidance, and mitigation.
If its more than that (think Saph with a spark on him, 11-14k hits WITH 2000 BV are common), then pure avoidance. I.E. I'd lost 10% block for 5% dodge in this scenario w/o questioning it one bit, as long as I was still block capped, I'd wanna push dodge/parry higher.
I've gotten as high as 28% block now, and as reasonable as 21%. It varies with gear, gems, enchants, and the like, I can range from 540-550 defense in gear mixtures, 28.5-30k unbuffed in all combinations.
naxx10, block value is lovely, I adore it, I love it for 25 man for the most part too, but I'll commonly switch from T7 helm to Thane's or something with more raw avoidance in favor of the block on T7
_________________
