Long ago I came to the conclusion that if every student and instructor fully realized just how dangerous a knife is they would run away like a striped assed ape, if possible that is. Similarly on numerous occasions I've asked instructors "does a knife scare you" only to have them answer "no, I have confidence in my skills." Usually I flinch when hearing these words because if the truth was known the reason they're not scared of a knife is because they've never encountered one outside the dojo. Hence these are the people to avoid at all costs along with their youtube videos and fact filled books which are marketed by (name your publishing company). Sorry folks, but martial arts publishers are more interested in earning a buck than protecting your welfare, buts thats a topic for another day. My point being is that inexperience and missinformation lead to disasterous results.
Inside the dojo everything works, no matter how absured it might seem. Pressure points, chi, complicated knife and gun disarms, chi knife disarms, chi gun disarms, they all work, but then the good guys never get killed in the westerns either. Maybe shot in the arm, but never killed. Right? Right. Therefore since you’re the good guy learning karate in the dojo you’ll never get killed. Right? Wrong. A large majority of the knife drills presented are merely extensions of someone's empty-handed, step-punch-kick, training. There's no fluidity, no real intent, no real threat and an over all tendency to preserve the style's integrity instead of addressing the threat and how you will react to it. Also, there's a built in delusion that the karate-ka can easily disarm the attacker without sustaining injury because they study karate, kung-fu, Tae-Kwon Do, etc, etc. Such beliefs and mindsets are a recipe for disaster. For instance not long ago a young man who had just started karate wanted to demonstrate his gun and knife disarms to me. "Okay, I said" and with the gun defense segment I simulated holding a pistol and stood 8 feet away, which is short range for a pistol- but long range for empty hand. "Come closer" he said, "no way" I answered then said "bang, your dead." With the knife it was about the same thing, he wanted me to line up formal like we were bowing in, but instead I grabbed his shirt and executed a series of underhanded thrusts to his stomach, groin and lower back. Needless to say he was a bit upset because I didn't play by the rules, but that's my point. Someone armed with a knife isn't going to play by the dojo's rules, they'll invent their own as things progress. That's why live training is so important, along with stressing the fact that if they've got a weapon and you don't, you've suddenly ended up on the bottom of the food chain. Moral of the story is there are no easy answers and beware of someone who presents one because they’ll probably get you killed.