I have a bread knife that has a sheath, and if I try really hard I can pull off some pretty wicked fast draw techniques with it, and its not even curved! i think katanas need this change, also, if the katana user has a high enough wpf they should be able to draw their sword so fast that it releases a razor sharp current of air which can slice enemies in half from distances depending on their power strike. a character with 170wpf and 6 power strike for example should be able to cut the entire map in half.