Paid with a credit card and now I am paranoid about privacy — what worked for you?

BenResearch_OR said:

The version of this that has an answer is narrower than the version being asked.

This is where I part company with the consensus forming above. The objection nobody has made: this only works if the measurement is doing what we assume it is doing, and that assumption has not been tested here.

One concrete data point for the thread. If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way. Most of the apparent contradictions in these threads dissolve at that step.

TrialTracker_MD said:

The objection nobody has made: this only works if the measurement is doing what we assume it is doing, and that assumption has not been tested here.

Adding the part of the answer the thread has not reached. The mechanism and the magnitude are separate questions. Agreeing that something happens says nothing about whether it happens enough to act on.

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

Following on from ingrid_STO — and this may be the naive question:

What did you change at the same time, and can you separate the two now?

Closing the loop on my own question.

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.