I can see why you would consider what you call "mysticism", or metaphysical belief systems, a warning sign. However, the use of mystical text forms, which is what I was referring to in my comment, is quite unrelated to this kind of metaphysical and cosmological rigidity. Compare, say, Christian fundamentalists versus Quakers or Unitarian Universalists, or Islamic Wahabis and Qutbis versus Sufis: the most doctrinal and memetically dangerous groups make only sparing use of mystical practices, or forbid them outright.

Atheists and agnostics are obviously a more challenging case, but it appears that at least some neopagans comfortably identify as such, using their supposed metaphysical beliefs as functionally useful aliefs, to be invoked through a ritual whenever the psychical effects of such rituals are desired. There is in fact an account of just such a ritual practice on LW itself involving the Winter Solstice, which is often celebrated as a festival by neopagan groups. It's hard to describe that account as anything other than a mystical ritual aiming to infuence the participants in very specific ways and induce a desirable stance of mind among them. In fact, that particular practice may be regarded as extremely foolish and memetically dangerous (because it involves a fairly blatant kind of happy-death-spiral) in a way that other mystical practices are not. I now see that post as a cautionary tale about the dangers of self-mindhacking, but that does not justify its wholesale rejection, particularly in an instructional context where long-term change is in fact desired.