Is it really a matter of effective health ? With a boss than make 100K each 10 seconds, and savage defense that absorb 80K we have plenty of effective health, but mastery is still very good for the purpose of reducing damage taken. More than effective health, the problem isn't the ratio between the amount of one hit by a boss, and the amount absorb by savage defense ?
Anyway my question was more about Crit and mastery. Intuitively I assumed that in mitigation/survival way, mastery which is a defensive stat was obviusly better than crit which is first an aggro stat ( even if it procures mitigation via savage defense's procs ). Does these numbers take aggro in account ? Or what is wrong with the calculus made in the pages 1/2/3 of this thread :
[WOTLK 4.0] Bear Discussion
( about reforging of crit or haste into mastery, and what are the ratios between thoses stats ).