The reg in the article looks like one of the early plastic Aqualung octos.
I was on Bonaire a few years ago, and went off the back of the boat. My wife was having some equipment problems, so I helped her at the surface then we submerged. I got a bit close to the fantail and another diver went off the boat nearly on top of me. I never saw them, only felt the impact as the bottom of their tank hit my first stage. The high pressure hose snapped off flush with the first stage. I made a slow ascent and got back on the boat. According to my computer, it took about 3 minutes to get back to the ladder, and the last of the gas was hissing out as I climbed it. I've heard it can take 10-20 minutes to lose gas through the small high pressure orifice, but it certainly wasn't true in my case. The wife got a couple of pics of the free flow.
There were no problems breathing the reg on ascent, by the way.
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