Thanks for the examples:
acupuncture, meditation, aromatherapy etc. Low-carb diets were denigrated for a long time but they've been shown to work at least as well as other diets
None of these seem to fulfill 3. They seem to fall into the category of somewhat decent with lots of exaggerated claims and enthusiastic followers.
Fecal transplants are a great example, although wikipedia says that most historical fecal therapies were consumed, and I don't know if those work (doubt it). Also it doesn't really fulfill 2 - it was doctors that first pioneered it when it was a weird fringe treatment. And thinking something is weird/extreme and fringe is different than thinking its a crackpot idea. But still a good example.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)
3. Open Threads should be posted in Discussion, and not Main.
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