OK I missed that you meant "easily fixed" in the strictly mathematical sense, not in the practical, real-world application sense.

With statistics on human affairs, 99% of the hard part is not the math, it is applying that math to a complicated, heterogenous, and difficult to measure underlying phenomena. And in most cases, statistics alone will never give you a straight answer, the best they can do is supplement and confirm qualitative observations. Failing to recognize this is how you get all those unending media reports about how X is bad for your health. PG's post was at the level of one of those junk health news articles.