TL;DR: 5% of armour weight is added to effective weapon weight, all that armour= wpf and speed penalty. Momentum should be increased!This is meant to make weapon stuns less of a problem for heavily armoured chars, it will also make heavy armour the preferred choice for crushthrough weapons(isn't i already?)
Realism point: Plate clad arm is heavier than the same arm dressed in cloth there fore it should affect the effective wepon weight if possible.
Full Tincan(heaviest)=37.7 weight
1%=0,38 // Katana hits as heavy as Longsword
2%=0,75 // Longsword htis as heavy as Greatsword
5%=1,88 // Studded warclub hits as heavy as Bar mace
10%=3,77 // Goedendag hits as heavy as Mallet
What percentile would be good? 5%? 10%? or 0%