http://forums.sjgames.com/showpost.php?p=1962292&postcount=7 Kromm in house ruling them as deflections.
note that One Hand specifies:
- you may make unarmed parries with a handless arm, and possibly strap something to it
In GURPS, "parry" does not only mean "stop cold," or what most unarmed fighters call a "block." It can also mean any slight deflection good enough to let you evade an attack with a partial step smaller than a hex on a battle map. A matador with a cape "parries" a bull. He doesn't stop the horns with his cape . . . he uses his cape to guide the bull past as he turns. That's what most parries are in GURPS. Hard meet-force-with-force parries aren't normally assumed. This is why even though weapons can break on any parry in real life, we only make that possible in the game when there's a factor-of-three weight difference.
- Reach: 0 for Reach C; +1 for Reach 1; +2 for Reach 2; and +3 for Reach 3+. [More surface area means it's easier to intercept a blow.]
- Balance: -1 if the weapon is unbalanced ("U" on its current Parry stat); 0 if balanced (no "U"). [Better balance means faster response to attacks.]
- Hand-Guard: -1 if the weapon lacks one; 0 if it has one of any style (basket, cross, tsuba, whatever). [Hand protection means close calls count as saves.]
- Surface: -1 if limited (blows must be received on a strong point, on or near the hilt, on or near the head, or whatever); 0 if unlimited (blows can be received anywhere on the weapon except where the hands are). [Using more of the surface area gives more options to defend.]
- Support: 0 if one-handed; +1 if two-handed. [A solidly grasped weapon is harder to push aside. This is 0/+1 instead of -1/0 because it's intended to balance against weapon-and-shield, where shields give a bonus.]
- emphasis: Support is a straightforward "two hands are stronger than one" thing. If we say adding a hand to a one-handed weapon gives +1 to Parry (and we do, in GURPS Martial Arts), then it should work that way in general.
- Flexibility: -1 if non-rigid; 0 if rigid. [A rigid weapon is harder to push aside.]