Weapon DMG and rounding error

[battins]

Wpn Dmg mod = (STR+Offense)/100 (minimum value of 2)
Bonus Damage modifier based on character level, class, weapon damage, weapon delay if 2h

(Wpn Dmg Mod * Weapon dmg) + Bonus Dmg Modifier = Max dmg

When you are rolling for damage you are taking the dice value to a lookup table to find the real value. Damage isn't 0,1,2,3,4,5,6,7,8,9,10 scale. It looks more like

miss 0-1
dodge 2
parry 3
very low hit 4-7
low hit 8-10
average hit (11-14)
above average hit (15-17)
max hit (18-20)

with the particular lookup table being affected by both characters AC/STR/Offense/Defense/Dodge/Block/Parry/Riposte/weapon skill. I read somewhere the maximum amount of the table that can be any category can reach is 75% (so worst case 75% miss, best case 75% max hit)