And I maintain you have not sufficiently shown this to be the case.
I also maintain that your willingness to override requirements without said override being explicitly stated has ramifications well beyond this simple power.
As an example:
Resistance no longer works, because damage must be mandatory.
Spirit Companions no longer works, because damage is still mandatory.
Being hidden and not in the attacked square no longer works.
More importantly, if you suggest that it is not the permissivity or the word 'can' that your argument hinges on, then you then propose the preposterous argument that stuff that crits on a range of 19-20 also hits on a 19, simply because there is no ability that exists to say otherwise.
So, if no ability exists to say Holy Ardor does not hit, then no ability exists to say that ____ Mastery feats do not hit.
The only difference between them is that Holy Ardor is based on an event unique to Oath of Emnity, and that the other is based on a range of discrete numbers.
The only rule that exists regarding discrete numbers and hitting without comparison to defense is natural 20. The rules -do- say, however, in situations that can occur where that exact number is not rolled, the hitting without comparison to defense cannot occur. It only asks that situation -can- occur. It does not refer to specific, discrete numbers.
Therefore, a range of discrete numbers is not necessary to satisfy Precision... only the fact that it can happen when not a natural 20.
Therefore, if you cannot hit with Daggermaster on a normal miss when you'd otherwise crit, you cannot do so with Holy Ardor.
Holy Ardor is a new kind of rule, but it has yet to create an unexpected situation. That's what matters for 'newness.' Otherwise, Oath of Emnity would never crit, because it -too- is a 'new rule.'
Well, I disagree and maintain that the new mechanic plus the new rule for it stand on their own as complete. That's the most straightforward way to read it.
You've not established the new mechanic creates an unaccounted for situation. You've not established a new rule for resolution -even exists-.
Therefore you're creating something out of nothing here.