System Toolkit page 67 provides the scale mechanism for attacks and defenses between enemies, groups, etc. of different sizes. However, I am not sure how to interpret the inner "or" (ie the "that" or "within the two effects).
Especially if it means applying a bonus to the attack or Defense, this means that only one of the two can be used within the same role (since one of the attackers and the other is a defender), or that means that the side that benefits from +2 damage should do so Not get the damage reduction in the the same conflict? (The same question applies to the attack / defense skill bonus.)