Dr.NateNeph said:

One practical note: write down what you did and when, before you need it.

Genuinely useful, thank you. I had the facts and not the framework. Sending this to two other people who asked me the same thing last week.

From the other side of the consultation, briefly. The distinction that resolves most of these threads is between what is true on average and what is true for one person. Both are real; they answer different questions and get quoted as if they were the same one.

Ask again with the specifics and you will get a better answer than this one.

james_edin said:

The distinction that resolves most of these threads is between what is true on average and what is true for one person.

Same pattern here, and in the same order. The detail I would add is minor and it is already implied above.

james_edin said:

The distinction that resolves most of these threads is between what is true on average and what is true for one person.

There is a second half to this that has not been said yet. 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.

Reporting back.

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.