The alternative perspective, however, is that mods should not add damage. Games4kickz put it this way, before going back to a16 because he was bored with a17: "Mods shouldn't add damage just because you put them in your weapon. They should add specific effects, like setting zombies on fire, or slowing them down. Improved damage should come from improved quality." (paraphrased)
I'm not saying that's how the game should work, but that mods add to damage is a choice, not a required mechanic. We can have mods *and* not have them add extra damage, which would allow extra damage to come (again) from quality.