I think you’ve made some very solid points, and I stand corrected.
Let me try to phrase myself more clearly.
Most things in GD cannot be looked at in isolation; similarly we must understand offence/defence in tandem. That is not to say that all builds prioritise the 2 equally.
In the setting of adcth, the priority of most builds is DPS. I think this is indisputable.
The only reason why adcth gets such good returns for the little bit of investment is because of the heavy investments into offence.
In other words, the spec relies predominantly on DPS to survive. Adcth just makes it easier.
A clearer analogy would be a CDR based build with 45% CDR stacking heals.
Are the healing procs the main source of sustain? No. It’s the CDR.
So similarly, a little bit of investment into skills like word of renewal, or devotions like behemoth will go a much longer way.
Turning our attention to builds which prioritise defence: ignoring lazy builds (@maya), these builds need to be able to face tank to dish out the pain.
The chaos DB spamming pyro with insane HP regen can consistently land direct strikes with DB on targets. The shield based retal warlord needs to get hit to proc rta. Etc.
Thus, in this setting, a small bit of investment into offence goes a much longer way than it would when compared to glass cannons.
EDIT: so why don’t I want IHE to affect HP regen?
Because it would make builds using HP regen as their predominant offensive/defensive strategy insanely broken.
2nd EDIT: just realised I forgot to respond to this specific bit
^me clearing naked with it
The only source of sustain outside of word of renewal is bat IIRC