Yes I was talking about commercial divers n not every dive is a helmet dive. During that unfortunate day, he was using a single tank attached to a harness and bringing some tools to another diver.
He had been diving for years and was a naval diver during his national service days however, on that day, he was over weighted, not feeling well and couldn't just drop the tools. He ruptured his ear drums as he could not control his descent
If he was on Scuba he should have known better, if he was surface supplied, his tender should be run off. Considering he was not willing to drop the tools or weightbelt, it is not clear if he would have used a hand for his BC either.
Back on topic, diving without a bcd is really a bad idea and unless a professional diving agency says diving without one is ok, I'll it to the brave or foolish
I believe you made an excellent case for never underestimating Archimedes Principal rather than that BCs are mandatory. Regardless of training or experience, diving stupid, even momentary, is what is dangerous. Physics is relentlessly reliable. IMHO, the "brave or foolish comment" is grossly overstated. Are you saying all the Scuba diving before the early 1980s foolish?