Have you heard about the
nocebo effect?
While an inert sugar pill (placebo) can make you feel better, warnings of fictional side-effects (nocebo) can make you feel those too. This is a common problem in pharmaceutical trials and a 1980s study found that heart patients were far more likely to suffer side-effects from their blood-thinning medication if they had first been warned of the medication's side-effects. This poses an ethical quandary: should doctors warn patients about side-effects if doing so makes them more likely to arise?
Well, yes, they should. But they don't need to scare people, and they can offer plenty of reassurance (placebo) to counterbalance the effect.
It seems to me that this has implications for the way we talk about the dark night. Firstly, just calling it the dark night conveys doom and gloom, besides referencing a belief system that includes an immortal soul and eternal damnation. When you consider placebo research, and how much very subtle things can effect significant clinical phenomena, this terminology could be detrimental. (In fact, it's killing you! You can't breathe Aaagh!!!! Jk.) If we call it what it is, dhukka nyanas, it would invite discussion of the meaning of dukkha. That in itself would lead to some skill and insight to help advance beyond them. Dhukka is a nuanced, flexible term. You can't really use it without understanding a little about how fear/misery/disgust arise as mental fabrications. This already has some reassurance in it. The term dark night, on the other hand, has a tone of finality and doesn't really teach you anything other than that you're screwed! You were born bad, you pooped your pants, and now you're going to pay!
My take is that the real danger is chronic yogi syndrome. If you're practicing well, you are on your way through and beyond dukkha forever. If you're not practicing well, then you are bound to be afflicted with dukkha forever. So rejoice, sheeples! Jk.
I've yet to come across any dire warnings from traditional sources. From the Buddha on down, they just say, this way freedom lies. If our practice is really *causing* so much misery, perhaps we're doing it wrong? But I suspect it's just that we live in a litigious society and are addicted to disclaimers and warnings. (BTW: lightning bolt + WARNING + Dark Night = nocebo effect. Maybe some pretty clouds and a drawing by Jane Rainbow wouldn't be so bad afterall?)
(There's
a funny caveat to the nocebo story. Turns out, only 8% of all clinical trials report the ingredients of their placebos. It's common practice for them to use active ingredients that mimic known side effects of the med being tested, so the side-effects don't show up as much in the final results. So, even if you do experience adverse reactions, you're likely to be told you're imagining it anyway. Bizarre.)