Re: Live tanto in grading
I've seen it done. My only observation is that each time I've seen it done the attacks were worse than if they were using a wooden or rubber tanto. The attack slows, the attack is totally telegraphed, and the end result is even less realistic waza. So any perceived "benefit" of using a real blade is more than offset by the fact that the practice is basically worthless. The *intent* of the attacker is what matters. And without strong, committed intent it just doesn't matter if the knife is real or fake. I'd rather have an intense, totally committed "that's gonna leave a mark" attack with a wooden or rubber blade any day.
If you want to get the level up, do the markers and t-shirt thing. But using a real blade will only give you one of two results. One is that your attacker won't give it everything they have so the practice teaches you *less* than just training with a rubber blade. Or they attack you for real and eventually someone ends up lacerated.
Whenever I see it I just think of people getting false confidence in their abilities. And Darwin Award candidates. All apologies to those who do it, but I must say I think it is really a dumb thing to do.
And just dropping a blade can cause a serious injury. I know guys in my craft who've dropped tanto on their feet and had the blade pierce through the shoe, through their foot, and into the floor. I work with live blades day-in and day-out and I get bothered by seeing people handling bokken improperly. If you want to see me go ballistic, start fiddling around with a live blade.
State of mind is what matters. You are training so your body learns how to move when it is for real. Train and train some more. Have them speed up with the wooden or rubber knife and mix up the attacks. That should get your adrenalin going more than enough.