I have seen many many times where guys completely disrobe for a weigh-in. Hell, I did it often when the I knew that I was close.
Put it this way, if you were like 3 ounces over weight and you could either drop your pants or go jump rope or run to sweat, then dry off and then weigh-in what would you prefer to do. I dropped my drawers the same as just about any other fighter will. Like I said, its very common.
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