"There exists no rationality curriculum such that a person of average IQ can benefit from it" and "there exists no rationality curriculum such that a person of LW-typical IQ can benefit from it" are not the same statement.

And there are some not entirely healthy subcultures around extensive meditation practices (detachment from the physical world as in "the only difference between an ideal monk and a corpse is that the monk still has a beating heart" and so on), which might be trouble for someone who really wants an algorithm to follow and grabs on to meditation without having much of a counterweight in their worldview.

shrug It sounds as though you want a rationality curriculum to fail, given that you are brainstorming this kind of creative failure mode.