So first, short question: Villains have no skill ranks, so if you make a duelist villain, how many wounds does he inflict on a Slash/Parry maneuver? (As those say you inflict wounds equal to your Weaponry skill.)
Secondly, while looking for an answer to this question I came upon this post on the (un)official forum. It got me thinking. I agree with this post in that Duelist maneuvers should not apply to Brute Squads, it's a different kind of combat than dueling and being able to dispatch 10 brutes alone in a round is ridiculously out of sync with the game. It makes them completely useless. But what about the idea that Duelists are hilariously broken? After all, the "Doctor" brings up a good point about how bad the balance can be? I suggest giving every "martial" hero background the "Student of Combat" Advantage from Heroes and Villains, and possibly allowing the Duelist background to have an additional advantage based on their style to even it out.
Would this completely break the game? Do you disagree that Duelists are broken?
EDIT: broken is a bit much, more accurate to say Duelists are unbalanced, and that is subject to your goals in the game.
Any effect that is based on a Skill or Trait Rank (such as Wounds inflicted by Duelist Maneuvers) uses half of a Villain's Strength. So a Strength 10 Villain would inflict 5 Wounds with Slash.
Next, there's a lot here to unpack.
First, 7thsea2e.com is NOT an official site. It's a fan site, nothing more.
Let me repeat that, in case there's any ambiguity. 7thsea2e.com IS NOT AN OFFICIAL SITE.
Second, Duelists originally could not use their Maneuvers against Brutes, but quite frankly it was less fun. I don't think there's anything wrong with either approach that you want to use.
I disagree with the idea that Duelists make Brutes "completely useless," but even if that were true I'm not sure it's a problem. I don't think Duelists should be particularly challenged by a group of 10 nameless, faceless town guardsmen. Inigo Montoya would be unimpressed by them, and I don't think it's out of tone of the genre for him to effortlessly defeat 10 men of that caliber.
On top of that, I don't think "more Brutes" or "make Brute Squads dangerous" is the answer -- I don't think ANY Hero of a martial bent should be particularly challenged by a Strength 10 Brute Squad. Hell, a Hero with "Reckless Takedown" can deal with them without even having to spend a single Raise and just move on with his day.
Brutes are speed bumps for Heroes, one aspect of a challenging situation rather than the whole of the challenge. This can change when you add in special Brutes (a team of 5 Assassins jumps the Duelist -- they go first when the GM spends a Danger Point, so they just lay a Dramatic Wound on the Duelist before he can do anything).
Would not letting Duelists perform maneuvers against Brutes completely break the game? No, absolutely not. Brutes would simply take more Raises to deal with. I don't think it's a good solution, though -- Duelist Academy is a five point Advantage, in fact the only one that can't situationally be purchased for less than that, so it should pack a BIG punch.
Do I believe that Duelists are broken? No, because the game works perfectly fine with them. Unbalanced might be a more accurate term for the question that you're asking, but I don't think they're unbalanced either. However, many do feel this way and I can see their perspective on the matter. Duelist Academy is an INCREDIBLY strong and rewarding Advantage (though for my money, "best bargain for cost-to-power" goes to Sorcery).
I believe the biggest complaint against Duelist Academy is that it's sort of a bottleneck Advantage -- martial characters without a dueling style struggle in combat much more, and there isn't a lot to compete with it even if you're willing to pay the same point cost. This is addressed quite a bit in upcoming sourcebooks, particularly NoT1 and NoT2, which have a lot more in the way of martial Advantages that let non-Duelists in on some of the fun.
TAJ-07: Technopriest And Justicar Of 7thSea2e