One thing that is still open after PharmHunterJen’s answer:

How long did you give it before you decided it was working?

labquiet_amy said:

Practical: whatever you change, write down the date and the reason.

Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. Pushing back on the anecdote-stacking. Twenty people reporting the same thing is twenty samples from the same self-selected pool, not twenty independent confirmations.

If somebody has the primary source to hand I would rather cite it than paraphrase it.

labquiet_amy said:

Practical: whatever you change, write down the date and the reason.

Agreed, with the usual condition: that holds for the average and this board is a collection of individuals. A population claim and a personal prediction are different things and get quoted interchangeably.

labquiet_amy said:

Practical: whatever you change, write down the date and the reason.

This is exactly what I could not find anywhere else.

OP back with an update, since a thread like this is useless without one.

Following up because I said I would. I changed one thing, left everything else alone, and waited the full interval before looking. It resolved, and I cannot prove which half of that did it.