i agree, but you yourself said the anonymous poster is making "quite thoughtful and trenchant" comments, and s/he does point out other corrolations and possible causes, as do others in comments on this post, so there's not a lot of goalpost moving, and your railing against those who only use "corrolation does not mean causation" as an excuse (as is your right, as it's your own post) is a little confusing in debating/refuting said anonymous's points, if that's what you were trying to do.