But the point of systemic thinking is to see when you've hit an area that's vulnerable to human and training factors and try to do the best you can to reasonabl

But the point of systemic thinking is to see when you've hit an area that's vulnerable to human and training factors and try to do the best you can to reasonably remove the risk. There are surely hazards that have caused less loss of life that we still consider dangerous at N=0. Do you know whether ATC large plane same-size spacing guidelines around airports have changed much over the years? I don't know whether airliner spacing would have generally increased or decreased, but I'd be surprised if it hasn't changed at all. Edit: I read more about these flights and I think I agree with you that I'm overstating the risk to airliners from wake turbulence. I was expecting to find increases in separation distances in response to the American flight and instead it looks like the only change made was a training change for rudder control.