It might be a case of the percentage not fully representing all perk bonuses both of the participants have.
I know that with high attack there is even no need to look at the percentage you almost always hit.
So far there were like 2 times when something felt off like my sellsword suddenly becoming unlucky and just can not hit the same target. Untill something changes like you swap the weapon or attack other target once or move someone into the zone. Like the guy just getting stuck on missing.
But that happened only few times in my experience. Probably just a mind trick(attention to wrong >>>> than to right).
