I can’t seem to gain any XP in the Piercing Weapons skill category. I tried testing with a pointy stick (tried a glass shiv as well, but they kept breaking when I used them in combat) and I couldn’t gain any appropriate piercing weapon XP. Although, I still gained normal Melee XP from the fighting, just none from the weapon category.
Bashing and Cutting weapons still give the appropriate weapon category XP, though. I’m posting it here mostly to confirm from others if this is also happening to them.