Even in that, you've combined several points. What if the practice methods haven't changed (same techniques, same training methods), but the philosophical approach has evolved or been lost entirely? Or vice-versa? What if it has all the ritual (bowing, uniforms, terms from origin language), but has evolved in every other way?I have been thinking about the name of this topic and the many posts about trying to define the two "types" of MA. One consistent theme I hear when non-traditional people talk about traditional styles is the following of specific protocols, philosophies, and decorum. Often it is not acknowledged that many of the techniques used in modern MA originated from a traditional format and conversely there have been many refinements, and new techniques along the way.
One line of defining a traditional style is one that it follows ALL the practices from a historical perspective, regardless of whether there have been changes within the mechanics over time. Likewise, a modern style may be one that has over time, or from origination dropped the decorum and philosophy to streamline their practice.
Possibly a streamlining method could be to peel back a style to the original known name (in last 200 years?). Not an ancient name/style that is thousands of years old because, let's be honest, we know basically nothing about them with the exception of a few possibly books. So there would not be ITF, ATA, WTF, etc... Tae Kwon Do. There would just be TKD for example. TKD alone is a tough one because in its current format it is not that old.
Hopefully this is a start that can be considered, deconstructed and refined.
This is what I was getting at earlier with the inherent problems in creating a definition across all these areas. Pretty near every style will have some things on each side. I can't think of any style where everything they do is about fighting prowess - even MMA has things that are common and are more about sportsmanship (touching gloves to start the fight, for instance). We end up with a continuum, rather than opposing ideals.