I think most arts were quite “mixed” in their beginning days. Look at the pioneers of karate. They blended Okinawan methods with Chinese methods.
Chojun Miyagi of Goju Ryu took indigenous Okinawan arts and blended them with what he learned from his teacher (who learned from Chinese teachers). Miyagi went to China after his teacher’s death, learned more stuff, and incorporated it further into his own art. Miyagi died in 1953, so it wasn’t that long ago. All of the founders of today’s well known Okinawan schools did similar.
It was after this generation where everyone became purists, of sorts. Mas Oyama blended his Goju Ryu and Shotokan learning. He then incorporated some Muay Thai principles into his art after sending his top students to compete there. Then the purists came and were afraid of any change.
Then several of the Kyokushin big name teachers left in the late 70s-80s, incorporating changes into their systems. Some said they were bringing back the old was, others said they were evolving; either way they were paradigm shifts.
If there’s one constant in anything, it’s change. I think you get a founder of an art who changes and evolves the art in general, then a generation or 3 is afraid to change anything, then someone new comes along and makes everyone assess what they’re doing. The latest is the Gracies IMO. Give it a generation or two, and you’ll see another paradigm shift in the arts as a whole. History has a strong tendency to repeat itself in some not so immediately obvious ways.
