In the past, I've considered Simpson's paradox to be nothing more than an amusing quirk of statistics. But, the parent example has helped me to see that Simpson

In the past, I've considered Simpson's paradox to be nothing more than an amusing quirk of statistics. But, the parent example has helped me to see that Simpson's paradox is frighteningly inevitable. For example, a conclusion like: "People taking a particular drug have worse outcomes." doesn't reflect on the efficacy of the drug at all - because people choosing to take the drug are presumably in greater need. Same in the piloting example above - Alice is scoring worse only because she has the more difficult assignments (perhaps because she is indeed the better pilot).