There is a number of fallacies in the above paragraphs, unusually many for a smart person like Yvain, so I assume that his "60% serious" disclaimer was missing a minus sign.

More generally, while very interesting, I find much of what he writes on his blog substantially less logically sound (but also more light-hearted, which I enjoy) than what he writes on LW, to the point that I constantly have to remind myself they're the same person because I can hardly alieve that. (His writings on raikoh.net are somewhere in between.)