I don't know anything about the system so I don't know if the material is good or bad.
The name is kind of funny, because "Ka Jutsu" does not mean a system mixing Karate and Jujutsu. "Jutsu" means techniques, and "Karate" means "empty hand" or "Chinese hand," depending on the kanji. "Karate" as a martial arts name is actually short for "Karate-Do," which means "The Way of the Empty (or Chinese) Hand." I've also seen "Karate-Jutsu," which would mean empty hand or Chinese hand techniques.
"Ka Jutsu" is a term for some actual techniques that used to be taught, and "Ka" means "fire." Ka Jutsu refers to old military techniques of setting fires and using primitive explosives and pyrotechnics. LOL
Leaving out older mixed systems that have been around for hundreds of years (everything has mixed with somehting else somewhere down the line,) there have been many people in modern times mixing systems before the term MMA became popular, and even long before Bruce Lee. The various WWII Combatives systems often mixed Jujutsu, boxing, wresting, Judo, common street fighting, etc. and some of the instructors were doing this before WWII, teaching police and private citizens. Paladin has been re-releasing some of the old manuals by these instructors.
One system that has recently become popular due to the Sherlock Holmes movie is Bartitsu.
Others teach mixed systems without knowing it. I've seen Americans doing "Jujutsu" that are really just doing Karate with added joint locks and throws. I guess their teacher's teacher mixed some Jujutsu in what was taught and they thought that it was an entire Jujutsu system.
