Mace mastery causes damage to go down?

So playing a barb now at lvl 17. I have a Bloodrise and Stoutnail. Using double swing. Putting points into mace mastery causes the damage shown on the character sheet to go down instead of up. For both weapons. By one point. For both this level and the last. What’s going on?

Its possible you are mistaken and it went up by 1 damage. Or there is a bug. I wouldn’t take much stock in what the character sheet shows for damage because it is pretty inaccurate in my experience anyway.

you using a mace or a hammer?

or does this distinction not exist for mace mastery?

i know plenty of runewords that have been ruined cause the recipe works in maces but not hammers even tho a hammer is shown as being a mace in game (i.e. maul)