Ahhh good observation Pete. But it's not truly a "safety" issue is it? I think it's more of an employer/labor relations issue: the Lifeguard Union must be saying "Look. Our lifeguards are suffering from eye strain and mental stress. Do you realize they actually have to watch people underwater to determine whether or not they're ok? We need to cut that out...that underwater thing..."

I see the future for your pool Martin. In ten years, those signs will be changed to "NO SWIMMING"