By teaching people using arguments from authority, he may be worsening the primary "sanity waterline" issues rather than improving them. The articles, materials, and comments I've seen make heavy use of language like "science-based", "research-based" and "expert". The people reading these articles in general have little or no skill at evaluating such claims, so that they effectively become arguments from authority. By rhetorically convincing them to adopt the techniques or thoughts, he's spreading quite possibly helpful ideas, but reinforcing bad habits around accepting ideas.

My immediate reaction was to disagree. I think most people don't listen to arguments from authority often enough; not too often. So I decided to search "arguments from authority" on LessWrong, and the first thing I came to was this article by Anna Salamon:

Another candidate practice is the practice of only passing on ideas one has oneself verified from empirical evidence (as in the ethic of traditional rationality, where arguments from authority are banned, and one attains virtue by checking everything for oneself). This practice sounds plausibly useful against group failure modes where bad ideas are kept in play, and passed on, in large part because so many others believe the idea (e.g. religious beliefs, or the persistence of Aristotelian physics in medieval scholasticism; this is the motivation for the scholarly norm of citing primary literature such as historical documents or original published experiments). But limiting individuals’ sharing to the (tiny) set of beliefs they can themselves check sounds extremely costly.

She then suggests separating out knowledge you have personally verified from arguments from authority knowledge to avoid groupthink, but this doesn't seem to me to be a viable method for the majority of people. I'm not sure it matters if non-experts engage in groupthink if they're following the views of experts who don't engage in groupthink.

Skimming the comments, I find that the response to AnnaSalamon's article was very positive, but the response to your opposite argument in this instance also seems to be very positive. In particular, AnnaSalamon argues that the share of knowledge which most people can or should personally verify is tiny relative to what they should learn. I agree with her view. While I recognize that there are different people responding to AnnaSalamon's comments than the one's responding to your comments, I fear that this may be a case of many members of LessWrong interpreting arguments based on presentation or circumstance rather than on their individual merits.