Originally, I had wanted to write a reply to Shadiveristy’s video The Problem with HEMA, although excellent replies were made by Dave Rawlings, Martin Austwick and Matt Easton before I had the chance  . After giving it some time, I thought this was a good opportunity to address an idea that is present in Shadiversity’s video, and that I’ve heard from many other people as well.
HEMA treatises represent a deep well of useful and valid martial information, but there are often people who believe that their own experience with sword fighting is somehow more useful and valid than the information that can be found in those treatises, or the information that can be gained from HEMA instructors.
“You know what works best for you”
This is one of the most common reasons giving for mixing and matching techniques from different source materials, or techniques that are not from any source material. The rationale that every individual knows what techniques work best for them in a fight, and that therefore, they should use those techniques while not using any techniques that don’t work them, seems sound at first glance.
The practice of martial arts however; is at least in part the practicing of techniques that are new and that might seem uncomfortable or unusual at first. If a technique doesn’t work, the best option may be continuing to try to make it work rather than give up on it entirely.
If a technique doesn’t work for you, then this may be because you don’t have the right sort of build or height for it; or it may in fact mean that you simply don’t have the right structure or understanding of the technique. It may be that you are trying to carry out the technique at the wrong time, or the wrong distance, or that you haven’t set up the technique correctly.
With a certain level of experience, I think someone can say a technique doesn’t work for them, but without that experience, I think this excuse is a lazy answer.