Enmity Management, Do we want it back?

[Absurdity]

What this will look like in practice is the tank stance will only be used when busters are completely unsurvivable without the mitigation provided by the tank stance and ignored the remainder of the fight. The stacking damage cap will be the baseline damage and the tank stance will be in effect a toggle-able mitigation cooldown with a damage down debuff baked into it. It will be worse than the old tank stances that reduced damage dealt, because it will take time to ramp back up again.
There were no significant mechanics with the old stances, as virtually no one used them outside of the first few GCDs of the fight, and that was only to secure initial enmity.

Yes you will only need the tank stance if you don't have cooldowns to survive but this still involves decision making on when to use said stance specific to the fight you're doing.

And if you think trying to maximize the %crit increase from Deliverance through proper gauge management or dealing with the MP drain from Darkside weren't mechanics then idk what to tell you.