Thank you for this, SeaRat! For me this idea of "competent" divers vs "certified" divers ties together many of what seems like loose ends of this thread.
Certification does not equal competency. Of course it does at the time the cert was issued, assuming the instructor was ethical, because you have to demonstrate competence in order to receive the cert. That doesn't mean you remain competent, however.
In my case I received what I will call a "shotgun" OW certification - acquired over the course of a few days in a tropical environment. At the end we were what I would now categorize as "barely competent". We knew some theory, we knew how to set up our gear, we knew how to stay alive breathing underwater for a little under an hour, and we knew that the underwater world is magical. But all that we had time (and money!) to do at time was the OW dives, nothing more - and it was just a few days shy of a full year before we were able to dive again, and it took a bit to regain some of that "competence" on our next trip. The first dive of that trip was somewhat challenging, but 45 minutes or so of warm water, pretty fish, and several turtles later we were all good... Still barely competent, but happy at least
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In the case of one SB member who recently admitted in a post to diving totally dependent on the DM even as far as depth was concerned - that seemed to me like a conscious, informed decision made in an attempt to overcome a severe mental block about diving, and the dive was performed with the full consent and under the direct supervision of a licensed dive professional. I feel it is not my place to pass judgement on the decision, or her competence.
I do think that divers that are
habitually totally dependent on the DM are no longer competent divers in any sense of diving, assuming they were certified to begin with. I would say they have reverted back to "Discover Scuba Dive" level, despite their certification - or possibly even lower since even DSD divers are usually at least using a depth gauge to know how deep they are!
However, someone posted earlier to the effect that diving is a big tent, which I took to mean as very inclusive, and after six months or so on ScubaBoard I see what they mean. You vintage divers, CCR divers, cave divers, lobster hunters, purple urchin infestation fighting divers, etc - I freely confess that I as a strictly warm water pretty fish diver would likely not be "competent" if I were diving with any of you. We also have folks here that volunteer with DiveHeart to enable people with disabilities severe enough that they could
never dive on their own to experience the wonder (and therapeutical value!) of what we do. And there is no question that those "disabled divers" are more than welcome in our tent.
So can that big tent include "incompetent" divers under the direct supervision of a licensed professional? I think so. And if I'm ever diving in a group that includes one, I'm going to view it as an opportunity to test my situational awareness competence, so that I don't get so focused on warm water, pretty fish and turtles that I forget about the people I'm diving with!