I think he meant the "damage roll", so if your gauss pistol does 70 damage on average, but you rolled 10% and actually hit for 7 damage (before resistance and armor are taken into account), it would show 10%.
Kind of a way to tell if weapons are effective. I remember Meridian shooting something a few times with a laser (sniper?) rifle, not killing his target and going "this weapon is useless...", even though he may have rolled 1%,5%,2% on his damage rolls, meaning it has nothing to do with the weapon.
An option (in Extended) to adjust the % range for weapons would be cool too. You can make some weapons more reliable (ex.: AP bullets do 50-200% damage, to represent their armor piercing capabilities ensuring they always do damage)