Have you guys considered a momental damage system like warband? where in this case his swing at the very beginning of his pull would cause little damage compared to in the center of his swing? It makes sense because you have to build the force with the swing, and obviously a swing shouldn't have much force at the beginning or very near the end. I'd like to see a spectrum of damage based on when the weapon hits: less if it was dragged and more if it was accelled, or something along those lines. I think this would naturally make the combat more believable. (I am very much an average noob in this game though)
Keep in mind that momentum is not what is usually desired here. Momentum means that spinning will do more damage, as it would in real life, because more momentum is obtained that way. The reason spinning isn't prevalent in real fights is because you'd get shanked or otherwise grappled, something that's impossible with the game's rules and initiative system, hence why we have to use different conditions/rules.