100%. As an a local instructor who has taught there and every other crappy low vis lake you can think of around here. I would absolutely not teach more than 4:1 ratio. DMs are DMS, sorry but the bar is so low and often DMs have been divers for maybe a year. IMO, they cannot be counted on to help in an emergency. The basic math of when you add more people and space them out increases the distance from the instructor's line of sight of some students too far to be able to see and prevent accidents before they become full blown emergencies. The platforms are too small and the bottom is untouchable. It's not like a pool where you can circle 10 people around you, or even a sandy bottom in the ocean. I'd consider almost every cave diving class I've taught and participated in safer than the idea of teaching an OW class of 8, including multiple kids, with myself and a DM at the Scuba Ranch, fwiw.
Also 100%. I will refuse non class relatives as well and have at times separated significant others in a class. The extra stress and anxiety that an overbearing parent puts on their child is wildly unhelpful. The pressure I've seen husbands put on their wives, parents on kids to "just do it" when they're so overwhelmed with anxiety and fear is absolutely dangerous. This goes 100% our mantra of we don't pressure anyone to dive. Find any other type of training that allows parents in the room with kids and instructor. They don't and for a very good reason, so let's kindly stop with the "parents should have" nonsense.
Nonsense? What is sensical about having a child become lost, drowned and abandoned by your fellow "professional", certified instructor?
My point was.. "I would have". Absolutely, I would not let my child do a dive like that without my immediate attention.
If I had to search to find an instructor that agreed to provide a private class (and allow me to be in the water)- then so be it.
Separating adults, spouses or even parent/child
open water students is understandable, reasonable and probably very common, but again, that is not the relevant situation that I am describing.
However, for me (being a certified and experienced diver) I would be there for the open water class dives,
Just think how easy it would be for a 250-lb panicked student to over power a small 13-yr old girl? Even if your child is perfect, she is still especially vulnerable. They certify now at what.. 10 yrs old based on the best judgement of "professionals"?
In my opinion, NOBODY should be teaching pre-teen children to scuba dive in open water unless the child is quite literally exceptional. Exceptional in discipline, motivation, maturity, watermanship skills and also be intelligent enough to adequately grasp the academic concepts and apply them to life or death consequences. Kinda like the exceptional little kids who can ride motocross or do high level gymnastics - they ARE unusual.
I know parents and SO's can be a problem when training (especially in the pool) but it is not unreasonable for an instructor to have a good sit down with the certified parent to explain that they will be expected to STFU and be invisible (unless there is a life or death emergency involving their child).
I don't think I could be convinced that this is not the appropriate approach for certified (and qualified) parents who want to have their pre-teen or young teen certified.
I guess if this terrible incident is not enough to convince certified parents to at least consider, being present on an OW training dive, then I doubt I can formulate a more convincing argument.