. . .Dr. Glen Egstrom, who sadly passed away last year, did a study of buddy breathing. He determined that for a specific buddy team to be confident of doing it well in a real life situation, they would need to have completed 17 successful performances in training sessions. They would thus be confident of performing the skill as a team. He also said that team would need to keep practicing it, because the skill is perishable."
I knew Glenn and discussed this with him from time to time. First of all, I don't think the study was just about buddy-breathing. The paper covered what it took to master ANY skill. And the actual number was 17-21 times. But you're correct about the key word being "successful." Glenn's point wasn't you couldn't just make 20 attempts and when you got #21 correct you'd mastered the skill. It was only successful attempts that counted. (I thought I had a copy of the study - and it was likely done in to 60s or 70s - but I can't find it.)
I have only heard of one attempt at buddy breathing in a real OOA situation in the last couple decades . . .
Allow me to share a real-world buddy-breathing story from one of my students. The caveat is that this was from the late 80s or early 90s, and bear in mind that rental gear back then did not always have alternate airs/octos.
Married couple, no major problems in class. I routinely taught buddy-breathing and during the 4 3-hour pool sessions, you buddy-breathed multiple times in each of them. Sometimes stationary, sometimes on the move doing laps around the pool. I also emphasized that prior to any day of diving, you should review and practice your emergency OOA procedures before you got into the water.
Shortly after being certified, couple decides to go dive the Avalon Underwater Park on Catalina, where we'd done some of our training dives, to do some fun dives on their own. As background, he has a bit of a tendency towards seasickness. Also as background, one of things I always taught - but never had them demonstrate or practice - was that if you were underwater and thought you were going to throw up, keep the reg in your mouth and throw up through it. This is because there's an involuntary inhale after you vomit and with no reg in your mouth, you might inhale seawater, start choking or trigger a laryngospasm, and none of the would be good. Worst case would be the vomitus would clog the reg and you'd get no air back. But you wouldn't get water.
They're doing a dive, maybe 40 feet deep and in kelp, and it's a a little surgy. He starts to feel nauseous, it gets worse. he signals wife and realizes he's about to vomit. Camps the reg to his mouth and vomits through reg. Reg clogs. Drops reg from mouth, gives out-of-air sign (slash across throat) to wife, she takes a breath and donates reg to him, they face each other, get arm positions secure, do a couple of passes back and forth, each signals the other they are ready to ascend, and they do so, buddy-breathing on the way up, and glancing upwards to chart an untangled path through the kelp to the surface above. They surface successfully, inflate BCs, shake his reg out to clear it, confirm it works, discuss what happened, decide to resume dive, all continues without further incident.
Buddy-breathing is not a dangerous or difficult skill if it's practiced and kept current.
