I think there are a lot of activities where training situations are simulated.
As a long time coach certified in several sports by national agencies, I can describe the two most important concepts in teaching a sport, concepts that apply well to scuba instruction. The first is to make the activity game-like--avoid teaching players to do something that is different from what is done in a game. The second is to maximize the repetitions in order to maximize the skill learning. The problem is that these two concepts often conflict. The most game-like thing you can do is to play the game, but that will minimize repetitions--a baseball player can go a whole game without touching a ball. Maximum repetition drills are often very much not game-like. A good coach has to find the best balance, the activity that compromises each ideal the least.
To give an example, you will often see soccer teams performing the worst possible instructional exercise because it maximizes repetitions. Two players face each other and pass a ball back and forth. As they do that, they learn to stare at the ball as it comes to them rather than look away to see what they need to do once they get the ball. They learn to wait for the ball to come to them rather than come to the ball to beat an opponent. They learn to stop the ball right next to them rather than touch it to a space away from an opponent. They learn to pass the ball directly back the way it came, rather than quickly redirect it to another player. They learn to pass it directly to a standing player, rather than to a space away from a moving player so that the player can get it in a free location. Playing a full-sided game teaches the skill better, but it minimizes repetitions. A good compromise is to play a 3 v. 3 game of keep away. It is not ideal for either goal, but it is much better than the more extreme alternatives.
Scuba skill work, particularly CESA instruction, is much the same. In the pool, we focus on the skill work, maximizing repetitions until the student shows mastery. Much of that is in conditions that are not dive like. We can improve that by refusing to put students on their knees, but it is not as good as an OW situation. The horizontal CESA is an example of a situation in which we do our best to make it game-like, but our limitations due to pool depth are such that the effort is counterproductive, like the soccer passing drill mentioned above. That's why we do it vertically in the OW dives, to try to get it into more of a game-like setting.
I don't think anyone has argued that vertical CESAs are unsafe (if ensuring exhalation), just that student shouldn't be doing bounce dives.
Actually, Pete has said that repeatedly. He has said that repeated CESA training is harmful to the instructor. He has been challenged to provide research indicating that his unusual claim is true. He has not done so, and has instead demanded that others show evidence that it is not true.
---------- Post added December 19th, 2012 at 09:37 AM ----------
Yeah, I don't believe this at all. My #1 job as an instructor is to supervise students and insure that they do no harm to themselves, others or the environment (in that order). That being said, when my students are in complete control of their trim and buoyancy, then this becomes an incredibly easy job. I find that some instructors feel that the only way to control their students is to plant them on the bottom. This denies the student valuable time to assimilate good neutral buoyancy habits and makes the job of getting them to stay off the bottom all that much harder. The best way for the instructor to control their students is to teach them how to control themselves. Then, all you need to do is to supervise rather than do the dive for them.
As a caveat, I see trim and buoyancy as being the foundational skills. All other skills are built onto this foundation. That doesn't make them less important, it just means that they depend on being trim and neutral in order to be truly mastered.
Once again, we are misdirecting the response. It is not about kneeling.
Let's take the example I used when you responded along these lines--the alternate air ascent.
I assume from what you described that you you can manage a group of divers doing an alternate air ascent without ascending with each buddy pair because you can see each pair clearly at all times throughout the exercise regardless of where you are. A single instructor in a poor visibility scenario, such as we see using a platform in a quarry, must ascend with each buddy pair. Not only that, the instructor cannot leave other buddy pairs unattended at depth while ascending with another pair. Not only that, the instructor cannot leave a buddy team unattended at the surface while working with another buddy team at depth. It isn't easy.
