As for the 1 second issue. I believe you stated that being under for more than 1 second was potentially life-threatening due to dry-drowning, which is why you chose to be right beside the bath when your child was in, to scoop him up immediately should he fall.
That is correct.
If I saw my child gasping under water at a pool, I'd quickly grab her then too.
The key thing is, I would see them gasping because they would be in my line of sight.
I know you really, really desperately want to paint me as some panicky mother that just implodes the second her child blows bubbles in the bath. But I'm afraid that simply isn't the case.
I watch her because it only takes a second to be in a fatal situation, not because a second with her face in the water is automatically fatal. I know you understand this by now, and I'm exhausting my patience explaining this over and over.
At children's swimming lessons, the delay will be longer than a second unless th child happens to be right beside the teacher... 10 seconds from occurrence to rescue would seem reasonable... The same, if not more, time it would take me to pop from the next room.
Incorrect. You cannot see your child, therefore it is not the same. I cannot understate the enormous difference in not knowing your child is even in danger for 10 seconds, to seeing a child in distress and taking 10 seconds to get to them. Huge difference, and the fact that you think they are the same thing is a bit worrying.
Why is the pool scenario safe, and the bath scenario not?
Neither scenario is safe. Water is not safe. It never will be. But exercise precautions and follow safety measures and it can a pleasant and enjoyable experience.
To flip this question on it's head, you'd never in a million years walk away while your child is swimming in the pool and leave them completely alone. Why would you in a bath?