roulis, I think most can agree that Quantum Mechanics may not apply directly but, if I may, that is not what is being suggested.
I interpret Safetypee's remarks as the recognition and acknowledgement of both complexity and uncertainty that requires a change in approach concerning the question, Why do "accidents" still occur?
Safetypee is seeking a model for understanding why accidents occur which may be more successful than the present Newtonian (Cartesian) model of classical physics.
Rather than wagging a finger, shouldn't we take our lessons from where we find them when confronted with aviation's Gordian Knot, human factors?
We must examine experience in other, perhaps-unfamiliar ways because, as SP has pointed out, the old interpretations of how accidents happen are showing themselves as no longer able to carry the potential for strong change and improvement. What imagination as much as we need knowledge.
Cartesian approach has largely resolved, (we cannot quite say eliminated) the old problems of mechanical failure, weather, navigation, communication, CFIT and mid-air collision. That is, aviation has resolved these direct causes through changes in technology.
Despite coming to terms with direct causes, accidents continue to occur is a result of human frailties - errors in perception, comprehension, or other "normal", human incapacities in complex, rapidly-changing systems and environments in which accidents presently seem to unfold.