I used to train with this hardass in Florida, he was a Colonel in the AF who had spent a lot of time in Japan. He would vouch for Americans to go over and train with certain people, but only after you did his equivalent of shodan testing. I never did this part, but I'm told it ended not with the normal ass beating and endurance stuff, but being made to eat a hellish curry and then do a shot of, you guessed it, Malort.
I get the curry but the Malort that is just fucking evil. It's basically war crimes in a bottle, pretty sure Carl J was a sadist.
My own single encounter with it was much less glamorous, done wholly at the dare of a female I was trying to impress. It didn't end well at all.