Thanks but I as referring to all the hand sculling in the open water clips (about minute 2:40). Wouldn't be surprising for a beginning diver, but. .Momentum and inventory is my guess. Yokes do the job and there are so many regulators, spares, and valves spread all over the fleet that converting to DIN would be hard to justify. And then there's all the manuals... the military has manuals for everything.
Maybe, but it looks about right to me. It's a harassment dive in a 10' pool so there's a lot of fast unpredictable moves.