Witch Hunter and Concentration question

Hi there, I find the Concentration mechanic interesting but from the current wording it seems weak for endgame content.

If you take Witchbane (Enemies have Maximum Concentration equal to 40% of their Maximum Life. Break enemy Concentration on Hit equal to 100% of Damage Dealt. Enemies regain 10% of Concentration every second if they haven't lost Concentration in the past 5 seconds.) in combination with No Mercy (Deal up to 30% more Damage to Enemies based on their missing Concentration.), how will they work with boss phases?

Best case scenario you deal up to 30% more damage for the first 40% of the boss's life and after that a steady 30% if you keep pumping damage at least every 5 seconds. That's already kind of quirky but since the Witch Hunter has Decimating Strike (initial hit takes between 5 and 30% of monsters life before the actual damage of the hit is inflicted), there's a way of getting started relatively quickly with Concentration.

But that 5 second counter is very bad if it still ticks during boss phases. Especially if boss phases don't also heal the boss (as your Decimating Strike can no longer help). Not only do you lose damage, but you also lose the defensive aspects of Concentration.

Does anyone have any insight on this?

Cheers!

TLDR: I really hope Concentration recovery timer stops during boss phases.

Would you be able to post what you can get about how Concentration works? I don't know either.

I would think it works exactly like the timer for Energy Shield, so if that recovers on boss phases, I would think Concentration also does.

Bump. Has anyone got a link to someone testing this ascendancy?

Well i fought Xesht with WitchHunter concentration and he fires his skills all the time he don't need cd i guess, even worse he uses the dedliest ones more frequently than without concentration. Looks like mega usless ascendancy, probablly only works on rares and usless mobs that die with one hit anyway.

It's crazy to me we dont have a good explanation on concentration from the devs. This ascendency either sucks or is poorly coded.

What is badly explained ?

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I am using both medium talents right now, and in my experience,
the bosses that have phases during which they are able to regain full energy shield, still aren't able to start regaining concentration (except for a few times where I screwed up). And then they would still need twice that time not getting it to get it back to 100%. Which is even more rare.

And I presume that (up to) doubling cooldown times, especially in the last quarter of boss life, makes for an even bigger of a difference, though I haven't really paid attention to whether that too works properly.

And are we absolutely certain that they work with Decimating Strike ?