I've seen dozens of people pass out from chokes/strangles. Recovery time can be anywhere from 1/4 a second to 20 or 30 seconds, as long as the pressure is removed. Either way that's you finished for the night. In 1984 an English Judoka killed a French fighter (I think he was French) because he choked him out on the way to the ground and then held him...it was the ref's job (they said) to spot that the guy was unconcious. They brought him back to life, luckily. So in this case what it comes down to is integrity. Yoshida afaik was an Olympic medallist so he would know easily if someone was passing out....tricks dont really work at world class level, especially on the ground. Yoshida wasn't taking the strangle off, he was telling the ref the guy was out. It's all passed now of course, but it ain't cool to say that the guy was lying about it.