I view it as quite safe even without cave training."... "Would be very difficult to get lost unless a diver purposely tried to."
Respectfully, I disagree. I don't mean to be argumentative, but I don't believe what you are advocating is in the best interest of OW divers. To each their own, but I hope the population of OW divers tempted to enter the overhead will NOT.
A cavern is truly a cavern only as long as you can see daylight. I've been "lost" in a "cavern" at 15' with the exit almost directly overhead - sunshine on my legs but not in my eyes. It was not a happy feeling.
I started cave diving in 1976, retired in 1992. NACD and NSS-CDS certs (but only PADI OW). Now I'm old and lazy, and like to dive in the warm, clear blue with all the fishies and my girls.
Neither I nor my family will participate in ANY overhead diving without appropriate equipment and planning (A dive guide to lead does not constitute planning). This includes things like HH on Bonaire, Calvins Crack, Ginnie Ballroom, etc.
I understand that this might seem a bit extreme, and I do get funny looks from DMs when I decline the swim-throughs and we go over the top - and some "aw Dad"s when we get back on the boat.
Oh, and the reason I quit cave diving: I got stuck in a zero vis silt-out and it scared the shxt out of me. I still have cold-sweat nightmares about it, and that was 20+ years ago.
A cavern can (and has) turned from a cavern into a zero vis silt-out cave instantaneously. I don't wanna be there.
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