Hmmm, this doesn't quite ring true. Maybe put it that the fighter is trained to make blows in such a way as to simultaneously guard against enemy attacks, whereas a rogue is focussed on making the attack count (preferably from a position where a counterattack is unlikely). This would have the effect (generally seen in D&D) that a fighter would do less damage, but would be better protected while doing so and, thus, less likely to get seriously hurt while they hurt the enemy.
I generally agree, although a combatant with brass knuckles (or any other situationally ineffectual weapon) against heavy armour should, or at least could, be looking for locks and disarms rather than punches.
I'm thinking 3E did the game (or at least the view of rogues) damage in this regard. In 3E, flanking is sufficient for a rogue to deal sneak attack damage. In 1E (I thought) a rogue needed to be hidden to use sneak attack (then called backstab).
Also, 3E took away a lot of the flavor / style difference between combat styles by factoring these into BAB (which is strictly comparable between classes: a +5BAB rogue fights equally as well as a +5BAB fighter, and equally as well as a +5BAB wizard) plus feats and class features, with the style differences shifted entirely to the feats and class features. (One of those class features is weapon proficiency. A non-multi-classed rogue has many fewer weapon proficiencies than a fighter. Which, as an aside, points out a weakness of 3E multi-classing, in that class features seem to be transferred too easily. A rogue/fighter can sneak attack with any weapon as a result, not just rogue/finesse type weapons, which seems odd. You might consider this not as a weakness but as a strength of the system.)
From the 1E point of view, a rogue doesn't want to be in the fray. When faced with an aware, capable, opponent, a rogue ducks out of sight. In 3E, a rogue is a part of the fray, and simply looks to avoid the worst attacks, while maneuvering for position (to flank) to make sneak attacks.
I'm thinking a part of the difference is to consider swashbuckler types as a kind of fighter distinct from rogues.
But, from a style point of view, a rogue might be alright in a dagger on dagger fight in a shadowy alleyway. Against an armored fighter kitted with sword and shield, a rogue should do poorly. That would seem to be the traditional view of rogues.
On the second point: A "hit" with brass knuckles might make no contact, but do hit point damage. A part of what hit points represent is "ablative luck". That is, if on average, three good attacks are necessary before obtaining a solid, debilitating hit with brass knuckles, that might be modeled with brass knuckles doing an average of 1/3 of the targets hit points on a successful hit. Whether one, all three, or just the last hit actually connects is not known, that being obscured by the combat model.
Thx!
TomB