There is a big difference between something being 'the best group ever' and being 'an easier shortcut to rationality than digging through philosophical writings the old-fashioned way', which is how I interpreted this post. There is a community component to LessWrong that obviously isn't present in old books, but I don't think that's paramount for most people. For me, in the beginning, the Sequences were just a good way to read about interesting ideas in small, digestible chunks during my breaks at work. Now it's a bit more than that; LessWrong gives me a chance to post my ideas where they'll be criticized by people who don't have any social-etiquette reason not to tear apart my arguments. But there's a big difference between a group being the optimum, the best any group of its kind could be, which LessWrong obviously isn't...and between being the best out of all the options in a limited area, which is more what this post is claiming (I think).