Dr.Martinez said:The pattern that distinguishes a bad batch from an exit is behaviour rather than product.
Saving this. It is the first explanation that did not require me to already understand it. Sending this to two other people who asked me the same thing last week.
From the other side of the consultation, briefly. The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either. Those three things can all be true at once, and most arguments here are two people holding different parts of that.
james_edin said:Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik…
This is where I part company with the consensus forming above. Filing an objection on the n=1 problem. Personal experience is genuine evidence about one person and very weak evidence about anybody else, and this thread keeps promoting the first into the second.
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Shop Reference StandardsThe figures, for anyone assembling their own picture. Give anything pharmacological four weeks before you judge it, and give anything measured weekly a four-point rolling average before you call it a trend.
Happy to go further on any of that.
Moderator note: good thread. Keeping it here rather than moving it, because the question is general enough to be useful. Tagging this one for the weekly digest.