I take your point SASless.
All these "one in a billion" statements are dervived mathmatically though.
Two things spring to mind, bigger and heavier.
Aviation parts, and particularly helicopter components, are built as light and as weak as possible.
Thats probably the reason Sikorsky used titanium studs, lighter than steel.
Build in more overload, more safety features, larger saftey margin.
I re read your first post about the death toll, 33 in two weeks, id imagine the oil companies (who pretty much drove up the aviation standards single handedly) will have quite a bit to say on this matter and things may change from their side rather than the regulators.
It will be interesting to see how this might affect the EC175s production testing.