This was what was more or less thrashed out on [[Talk:Alternative medicine]] - that "alternative medicine" may or may not be rubbish, but is sincere; but quackery includes knowing deception. FWIW.
I don't see how this is a workable distinction. It's not the treatments that are sincere or not - it's their practitioners. I'm sure there are lots of sincere homeopaths - but who's to say that there aren't a few who know that the remedies don't work (better than any placebo) but sell them anyway?
Likewise, how do you know that [[Jomanda]] wasn't sincere and acting in good faith? And how can you know that practitioners of [[Chelation therapy]] aren't sincere? Both are currently in the quackery category.
Regards, Haukur