It comes down to what your comfortable with. Some people just pass out at the sight of blood and not necessarily the one thats hurt. Only warning you get, is thier knees wooble just before they go down.
I see flying alone , no different than spending the day in the woods alone with a chainsaw cutting firewood , or working in my shop with power tools. Safety starts with ones self.
The more people flying, the greater the odds are that Murphy is going to show up. So policing each other becomes a must , and I`m never offended when something is pointed out to me I`m doing wrong. Well as long as they don`t get in my face about it.