pete_nash said:

The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either.

Can confirm. Same sequence, different timescale.

raj_cambridge said:

Keep the original post as written when you update it, and add the correction underneath.

Coming at raj_cambridge’s question from a different direction. Whatever the answer turns out to be, the method for getting there is the same: state the assumption, do the arithmetic in public, and invite the correction. That is slower than asserting, and it is the only version that survives being wrong.

One concrete data point for the thread. Say what you would expect to see if you were wrong, before you look. It is a small discipline and it changes what you notice.

Happy to go further on any of that.

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

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

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