A narrower follow-up, since the general answer is now clear:

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

TrialTracker_MD said:

If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

Pushing back on TrialTracker_MD here. 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.

TrialTracker_MD said:

If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

Fair, and it stops being fair at the extremes. The middle of the range is well understood; the ends are where the honest answer is that nobody knows.

TrialTracker_MD said:

If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

Thank you for spelling out the reasoning rather than just the conclusion. I will report back once I have actually tried it.

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

Closing the loop. The answer turned out to depend on the detail I had left out of the opening post, which is a lesson about how to ask rather than about the subject.