It's literally just a matter of GCDs saved. If you save a GCD at the start, that is not somehow different than saving a GCD across 8 seconds' duration. It's still A GCD of healing.
Why would anyone open a trash-pull in this game with healing? You had the whole pre-pull to shield and HoT.(and in all likelihood if TBN was the first thing you hit because it's the lowest CD, any healing you do get while it's active would be overhealing).
Tanks could literally go without touching their short-CD miti whatsoever and that would still be irrelevant even in full pulls.Meanwhile the backend of that damage will still be a giant unlubricated spike.
Until such time as Yoshi come up and says "We won't change Dark Mind, Living Dead, or Oblation because TBN," this narrative is literally not sane.The issue isn't "TBN is bad, uniquely and individually." The issue is "TBN is insufficient to hold up the weight of everything DRK is giving up to have it."
If a given element is constant even as various other elements change, the constant, unchanging element is not going to explain those changes. It's like you've taken three different iterations of a given play in the same theater and decided to blame the last, lackluster performance... on the dimensions of the room. It's unchanged. It's not going to explain away changes.
We had TBN back when we were invincible in AoE by way of DA-AD. We had TBN back when we also had, on average, the highest single-target mitigation in raids. We had TBN back when DRK had head and shoulders more dungeon mitigation than PLD or GNB. If it coexists alongside those strengths, it cannot be the reason for those relative strengths not existing now.
TBN is not new to this expansion. Oblation is. If you are going to compare the power levels of expansion additions from PLD, WAR, and GNB, then compare them against what DRK gained this expansion. That new defensive capacity, by the way, is Oblation -- not TBN.
And let's be clear here: mitigation adds to existing eHP only for the duration of that mitigation. Unlike an actual healing buff, every bit of eHP it "adds" is removed at the end of that duration. If you want to make the claim that mitigation, effectively, increases healing received then you must also make the claim that mitigation decreases effective healing you had received the moment its duration ends.And the fun thing about the 82 abilities is they not only bump up that mitigation, but add to exactly those healing effects. A healing effect given under the effects of mitigation is multiplied EHP.
More precise would be to say that HP consumed over the duration of mitigation is worth more damage. For if it was not consumed over that duration, it will have already lost any predictive eHP bonus. Their frames of reference are different. HP is not limited to that 8-second duration unless generated and consumed within that 8-second duration.
And, again, Oblation is DRK's lv82 ability, mirroring Catharsis and Clarity, Resolve and Benediction, and Stem the Flow and Stem the Tide, not TBN.