![Bored :bored:](./images/smilies/dozey.gif)
I never noticed that weight before. 10 pounds is a bit ridiculous. I googled for weight of a two-handed sword and the range was 4-8.8 lbs, claymores being about 5.5 lbs.
Now, I don't know if the HP needs increased or decreased, since that is neither here nor there for when correcting a weight listing. RAW a katana is just a masterwork bastard sword. Not sure if the 10 lbs was a typo for Koumei since Dwarven Waraxe is 8 lbs per the SRD, so 5 pounds lighter would be 3, which is about right.