Tank Mitigation vs Tank DPS.

[Nedkel]

https://ffxiv.ariyala.com/19Y02 <- Here's your tenacity best in slot.

https://ffxiv.ariyala.com/19Y0K <- Heres your non tenacity best using the same ilvl.


The tenacity build gains: 5.6% mitigation.
The avoid tenacity build gains: 3.6% damage, .8% crit and crit damage.

If you think getting less than 6% eHP is worth ~4.5% damage, I dunno what to tell you, but its not.

Put tenacity melds with direct hit mix into the exact same gear

https://ffxiv.ariyala.com/19YCC - tenacity
1260dh, 1948 crit, 2200 det, 2648 ten
Here are the multipliers 3.65% x 7.1% x 7.3% x 6.8% = 1.272

Yours
https://ffxiv.ariyala.com/19Y0K
https://ffxiv.ariyala.com/19YC7 (you choosed wrong earrings)
2380 direct hit, 1948 crit, 2200 det, 1558 ten
8.3% x 7.1% x 7.3% x 3.5% = 1.288

Literally 1.6% damage difference, and 3.3% mitigation for tenacity one which would be more if we used ilvl 460 and higher with 2 melds slot in accessories.

So just dropping into explain, mitigation is multiplicative not additive, so for example in the old system if you had tank stance on as well as using rampart you wouldnt mitigate 40%, youd mitigate 36% (damage ×0.8x0.8) because of how buffs stack. So if in this case tenacity stacks like every other defensive buff, a 4% tenacity would actually equal 3% when taking into account the passive 20% (1x0.8x0.96=0.768) IE youve not been made 4% tankier

Yes, but if you compare a tank with and without this 4% bonus mitigation from tenacity, a tank with tenacity is 4% more tanky than a tank without it.
You will stand there for 4% longer and you will be easier to heal by 4%.
With double 20% mitigation, you will mitigate 1000 dps to 640, reduce it by 4% its 614.4 dps you will receive, which is exact 96% of 640 value.
Now if your tank has 10k hp, and you divide this by dps from above, tank without tenacity will die in 15.625 seconds, where tank with tenacity will stand there for 16.276 seconds, which is 4.16% longer.
A 4% is 4%.