Precisely.
I think the only possible "double-blind" method would be to make the dosage sooo low, that it wouldn't be noticeable, & therefore probably-wouldn't produce any medically-useful effect.
IF the only dosage that works, is noticeable,
AND there is a regime auto-reject, on any study where the difference between placebo & tested-psychotropic is noticeable,
THEN that rule-regime prohibits the entire category of such interventions, from ever being considered valid.
That isn't evidence-based-medicine: that, rather, is established-regime-based-medicine-that-IDENTIFIES-AS-evidence-based-medicine.
Quite a distinct difference..
Probably, what they need to do is use lowest-dose-that-produces-results & sooo many in the study that the statistics become undeniable..
There's another issue, though..
New Scientist reported, perhaps last century, that MDMA-induced-euphoria was permanently burning out people's ability to experience euphoria..
Which would explain the higher-depression-rate among former MDMA users nowadays, wouldn't it?
Artificially-forcing a brain-system .. does tend to have unfortunate consequences.
The "believers in MDMA" won't tolerate that to be true, of course, any more than ideologues/believers/prejudices in ANY domain would permit actual-evidence to interfere with their belief..
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