First holy heck, am I wordy today or what? But BlueSparkle asked so maybe somone are interested in the response. If not, then at last I get to think things through by writing them down, and read other people's interesting responses.
I'm not sure what I would do with my hands if I didn't clasp them... what would you (or beanojones) suggest as a good way to hold them? (Say, for these students.)
As you sussed it out, arms forward can allow for otherwise obviously counterproductive behavior to be masked. But it also goes little deeper than that for me.
The "As for me" answer is that as I am not a GUE diver/instructor, and I would rather have students not using their hands and arms for anything (picking their noses or scratching their butts is fine) that is not directly manipulating gear, or making hand signals. For both the "I cannot be sure what is going on" part, but for the bigger part, they are likely going to be trapping themselves in a bit of an "Instinct/fight the instinct" cycle. Stifling instincts creates noise and raises stress which makes the "zen" of neutral buoyancy hard to approach because it creates an "off the top of the lungs" breathing pattern. Plus even if they can fight down the urge to wiggle the arms, and they only use elbow out pose for stability, what happens when the hands are need to hold a light, of a camera, or a slate and a pencil, or their dive buddies hand, or their mask? If arms are needed for stability, then when they need to use their hands, where does the replacement stability come from?
I get why GUE wants the position because they want the gauges mounted on the wrist, and they are readying people for scooter use so they want the arms forward position stamped in. But IME (in teaching mostly OW to tourists), it just encourages students to use their hands as aerofoils/stabilizers which encourages them to at least start to attempt to use them for propulsion and/or stability. (At least I can see ) the students in the video rolling tension through their appendages as they do the instinctive (but counterproductive) thing and start to use their hands and arms only to remember to stifle themselves. It is because beginning divers will always want to use their hands that I emphasize to students that hands are the only to manipulate gear or hand signal. But to make the lesson stick I make sure the divers are completely neutral while doing other training stuff and watch the little arm twitches propel them slowly to the surface, because a truly neutral diver will propel themselves to the surface with the usual beginning diver arm motions, including obvious things like pushing up off the bottom with their hands, but even less obvious things like the rolling and twitching of shoulders and extended elbows in the pray position. The nature of the shoulder joint moving mostly below the plane of the body causes this. IME, Neutral OW students 'learn' without me teaching it that an arms forward position is counterproductive. It's why I generally make all hand signals right in front of my mask, and otherwise model arms at the sides. Elbows out just starts them into a cycle of instinctive twitching, and stifling the desire to twitch, IME. And that's what I see the students in the video doing, starting to move their arms to gain stability, and then stifling that urge. Any time there is that noise of "Oh don't do that" running through their heads, it is interfering with enjoyment, learning, fun, whatever. I want my students learning sometimes through solving problems their land instincts create, not learning though the repetitive act of stifling an instinctual urge to do something. First I just don't think that approach works: at the end of ten day course the divers in the video were still twitching their arms, because they are just stifling an instinct rather than giving in to the instinct completely, trying that instinctual approach out and seeing for themselves that it just does not work. The first time my OW students end up at the surface with their hand waving they will realize that the instinctual response to use their arms even just a little or even just as stabilizers is a non starter, because it is just too hard to overcome land instincts, even in a 10 day course. Stabilization is the job of fins and leg position. After the arm wavers/twitchers end up at the surface, I explain why they have ended up at the surface. If they want to keep ending up there, they should continue to use their arms. Only rarely do they even continue to leave their arms forward. When they do though, they tend to end up in the instinct/stifle instinct cycle, which in and of itself can mask slightly negative diving because even that ends up creating an upward force, that has to counterbalanced by staying slightly negative, which is counteracted by breathing off the top of the lungs.
Since I know that arm twitches cause student divers to end up at the surface, or at least sends them in that direction, I am making the further inference that while the GUE OW divers in the video are at midwater and temporarily neutral, they too might be breathing off the top which allows quick exhalation to correct for the upward propulsion of the arm waving. If they were truly neutral the twitching would probably send them up more. Perhaps I am overanalyzing, but honest, I have worked through this a great deal, and arms in front (for beginning divers) is just a non-started. They have not had enough time to remodel 20 years of above-the-surface life experience into appropriate underwater instincts. The main goal of an OW class is to create an experience in which we allow divers to see that their instinctual body motions (and even their proprioception), successful and correct as they have been to this point
on land, just don't work
underwater. (Yeah, and teach them how to do whatever with the gear. But that is all secondary busywork to creating divers.) And we need them to see heretofore successful land-based instinctual responses fail as quickly as possible, so they discard the instincts, and start practicing new behavior patterns that are successful. But to remove the instinctual response, sometimes we just have to remove the precipitating urge to use ingrained land instincts. In this case arms forward is just too inviting a pose. New divers can stop arm movements but only by keeping the thought "Don't use your arms, don't use your arms, don't use your arms" flashing through their forebrain. Instead of the "I love being weightless" and "Ooh pretty fish" that I want them thinking about.
Arms is front just seems to allow new divers to keep envisioning arm usage as functional in propulsion and stability. I see it in this video from beginning to end. (I think) I know why the arms are out there under the GUE system, but it seems like the GUE approach is to intellectually approach the symptom by telling people not to do it, and not address the root cause which is that beginners with their arms forward will try and use them.
