Armor weight
Armor weight modified proficiency = base proficiency * (1 - 0.01 * effective armor weight)
Effective armor weight = 2*head armor weight + body armor weight + leg armor weight + 4*hand armor weight - 10
(Source: WaltF4, updated 31.7.2012 based on the new formula)
This means that every point of armor weight with helmet weight multiplied by 2 and glove weight multiplied by 4 over 10 reduces your wpf by 1%. Or the same put other way, any effective armor weight from the above equation reduces your wpf 1% per 1 point.
Hey, my old 1h/2h/pole shieldercav (aka: The Weapons Master aka The Looter) build!(click to show/hide)
super hybrid! You are mediocre with all melee weapons and will suffer against more dedicated builds. It does however not make you useless in strat, there's always a melee weapon for you to use.