The weapon proficiency list file is to set what each weapon category a weapon belongs to (Simple, Martial, Exotic, Natural) so that PCGen can determine whether or not a character qualifies to use that weapon or not. The 1st field is the name field, there is no tag for it, just the name of the weapon proficiency.
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Tag Name: HANDS:x
Variables Used (x): Number (minimum number of hands required to use the weapon)
What it does:
Examples:
HANDS:2
Weapon is wielded with two hands.
HANDS:1IFLARGERTHANWEAPON
Weapon is wielded with one hand if the PC is larger than the weapon size.