After equipping the Adamantine Sword from Grymforge all of my weapons show the damage for that weapon if they are equal to or higher than that weapon. All of my NPC's also show max damage capped at 6-16. I've tried reloading saves (now that is about 35 hours behind me), making new saves, resting etc. and the damage numbers are just stuck at 6-16 which is more than a little annoying. In battle it does the correct amount of damage, but it is difficult to choose which weapon to use based on how they interact with your equipment, causing potentially swapping to a new item to take far longer than in should. And it's a bug. It simply should not happen (I know bugs happen, I mean it's obviously not intended to show the wrong numbers on the screen).