No. I am saying the amount of additional self-heal you gain via heal relic is negligible and cannot be relied on. It doesn't mean healers can heal you less. They will still use the exact same abilities which result into overheal done by them or your self-heal.
I have reached the point now where I simply don't believe there are ultimately 2 particular BiS relics for every possible circumstance.
You were referring to DtPS and HPS. But the reality is single hits are usually coming in certain time frames providing 1-4 second pauses of no damage taken. Healers also don't heal you via flowing heals all the time (except for abilitites such as Healing Trance or Kolto Cloud) but also either 3 sec ticking HoT or 1.5-3 second cast heal. So DtPS and HPS is fine to get an idea of what is happening overall but is not entirely real. For example, in TFB the last boss: your average DtPS after the fight would be 1000 (made up number), yet, you are not tanking the boss in the second phase for like 30-45 seconds. So, there is a time where your DtPS is let's say 2000 for 45 seconds and then 0 for another 45 seconds. How does the self-heal or HPS fit into that? Same for Kephess tank switch or Kephess the Undying second phase etc etc.
To comment on the 'doing something wrong'.. Almost every fight provides periods of time (longer or shorter) where you effectively don't tank (EC NiM: Sonic Paralysis, tanking Zorn while he does Baradium Toss, Defensive Systems on TT, Shield phase on Firebrand side, Vorgath field clicker, Probe tank when probe is not active, Kephess in between phases, when the other tank tanks the Bomber etc etc). Again, DtPS and HPS does not give you answer to anything in terms of certain parts of the fight.
Consider Sage HPS, the amount of HPS they get via Salvation. Very relevant huh
Healers can't control this effectively. They can crit + there is some RNG to healing numbers as well based on the min and max possible. This is just a funny thing to me.
So, what you're saying is that the HPS you provide yourself is mitigation? That's new terminology to me, but ok. Another thing. The self healing you do should make up for the additional damage you take because of lower armor rating. In ideal world maybe of course, but according to various logs of various people, it pretty much reflects this basic idea (factors such as having a competent player squeezing the most of their tank take place here and are very variable again).
Let me ask you one thing. The healing proc relic doesn't provide any additional benefit to a Shadow tank. So you consider it as BiS for every single tanking class?
This is just your statement based on your perception and it is incorrect. I am fairly aware of all the attack types of all the bosses and know it plays a huge role in learning how to tank different content effectively. Actually, this is the most important thing for a Shadow tank considering the nature of our cooldowns
I have never mathematically proved WH passive relic is BiS and never even tried to. Neither have you proven that heal proc relic is BiS - mathematically.