I just found this project namend “CLANG” about a sword fighting video game based on real physics, real-world techniques and proper martial arts in sword fighting performed in the late medieval times. It was funded on kickstarter in 2012:
It seems that their goal for a realistic sword fighting game is pretty similar to what Warhorse want to achieve for KCD (although with a different perspective). Apparently the developers of CLANG run out of money last autumn which is quite sad. But perhaps Warhorse could contact them to just talk about their views on the topic of realistic medieval fighting in video games or maybe even about some sort of collaboration? I mean it would be a shame to leave all that work already done on that field completely unused, don’t ya think?