1 endurance gets you 10.8*0.08 heals every 12 seconds = 0.072 hps
The slope for mitigation a a function of stat pool is 3.7e-5.
So dps*0.000037=0.072 will give the dps for which mitigation is better.
I think there is some crazy burst in 2.0. Even the hounds in mando raiders are rediculuos. I think mitigation is better ast an even trade. If you could get 2 points of endurance vs. 1 point of mitigation, then dps would have to be 4000. This is permitigation dps.
the math is interesting but how does it actually apply to tanking? with endurance is easy to calculate but with absorb/shield its different because its not straight up mitigation since its a % chance that mitigation will occur. So you would have to calculate in your %shield chance (54% with ward up) vs your absorb chance (37%) in order to see the direct effect of 1 point of mitigation.
currently my HP is at 34.5k buffed as a shadow tank which seems to be enough to cover the 55 HM FPs (not sure about ops) so il probably use absorb augments and see how things go.
Also on mando raiders your supposed to keep the hounds out of the bosses red circle... other wise ya they get crazy buffed lol.