Based upon the conversation in this thread http://www.7thsea2e.com/port/forum/duelists-vs-brutes, I have made the following house rule.
Brute Squads Strength is reduced by spending Raises not by dealing Wounds. A new Duelist Maneuver has been added and all Duelists get it:
Not all duels are one on one; fighting a group of armed men requires different tactics. When you perform Whirl, spend a number of Raises (minimum 1). You reduce a Brute Squad's Strength by a number equal to Half your Ranks in Weaponry rounded up plus the Raises you spend. You can use this maneuver once per round.
Going to give this a try at the next game and see...