We should get myth busters on this issue. Are machine folded blades as good as as hand crafted! It's a topic I wouldn't want to wager on. Specially since I am a Toolmaker/Machining Specialist.!
The very first episode of another Discovery Channel show,
Weapon Masters, already did this.
Really though, katanas are kind of crap for piercing armor anyway, so their base AP -1 makes little real world sense. They're slicing weapons, not bashers or stabbers.
Traditionally, in SR, weapon quality only comes up on a glitch, not in the general use of the weapon.
Final word: In 2070, machines have hands. So, hand forged and machine forged are really a blurred line.