Dr.EM_Chicago said:

Order of operations matters more than any single choice here: establish a baseline, change one thing, wait long enough for it to express itself, then…

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.

A1cHero_PHX said:

International shipping tracking for cross-border ordering orders: my experience with customs in the US when ordering from overseas: Required FDA…

Genuinely useful, thank you. I had the facts and not the framework. Adding it to my notes with a link back to this thread.

Dr.EM_Chicago said:

Order of operations matters more than any single choice here: establish a baseline, change one thing, wait long enough for it to express itself, then…

Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. I think the framing smuggles in the conclusion. Ask it the other way round and the obvious answer reverses, which usually means the question is doing the work.

Adding the numbers, since they settle part of this. Practical: whatever you change, write down the date and the reason. In three months the reason is what you will have forgotten, and the reason is what makes the record worth having.

Moderator note: the sourcing question belongs in the vendor section and has been split out. Report rather than reply if it drifts again.