[2020] Paladin mastery passive, how does it work?

One of our developers confirmed this is working on our discord server:

Trasochi: It works, but the numbers aren’t reflected in the character sheet for performance reasons (the actual amount is only calculated when you use an ability rather than every frame or whenever your health changes).

Krumkai: are you sure it’s working? I didn’t see much different in dps with 100% hp and 30% hp

Trasochi: It’s additive with other increases. For example if you have 500% increased damage from other sources, it’ll just be going from 530% to 600%, so you’d only be dealing around 11% more damage at full health than you would at 30% health.