I used to be a beach guard and in high school a pool guard and have taught WSI. The drowning response truly is not what most people expect, like the MOF thing, not to start that, but that is a voluntary action and drowning people generally are incapable of voluntary actions as they are literally embroiled in the act of drowning for lack of a better explanation. Several times I have responded to people in belly deep water who were drowning and so have others I know of the same thing. They are so involved in the drowning it is almost as if it was a willful act to the point they do not even realize they can stand up--and not drown. Not to be funny but people, children in particular, could drown in a hot tub etc.
You cannot--cannot--allow children into pools, tubs etc without constant supervision, they will drown in a heartbeat.
Here is a recent story, I swim laps at a local Y and the guards there are excellent and attentive. However, there were a bunch of school age children sometimes in the non-lap portion, even in the deep end. The guard was distracted I assume, because, as I swam laps and just before doing my flip turn I noticed a child and it caught my attention, I knew he was drowning, as I was some distance away, I did my flip turn, broke surface and pointed to the boy and the guard was in the water so fast I could not believe how fast he moved. I am sure the guard would have seen him in another few seconds, his fast reaction time tells me he was already having that "feeling".
This is not a human specific reaction, dogs will do the same response. They will literally drown before your very eyes without so much as a wimper, especially non water dogs like collies etc.
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