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

How would you tell the difference between that and the alternative explanation?

traveltech_sara said:

My HPLC chromatogram analysis for certificates of analysis — I sent my batch to Janoshik and here's what the results showed: Main peak retention time:…

Community-verified vendors for certificates of analysis: I maintain a spreadsheet of Janoshik-verified test results submitted by community members. Across 49 submitted tests:

• 78% tested at ≥98% purity
• 15% tested at 95-98% purity
• 7% tested at <95% purity (concerning)

The vendors with consistently high purity results are listed in the Vendor Directory. We update monthly based on new community submissions.

traveltech_sara said:

My HPLC chromatogram analysis for certificates of analysis — I sent my batch to Janoshik and here's what the results showed: Main peak retention time:…

Agreed, and the size of the effect matters as much as its existence. Something real and small gets treated here as though it were real and decisive.

I would rather be corrected than agreed with, if it comes to it.

traveltech_sara said:

My HPLC chromatogram analysis for certificates of analysis — I sent my batch to Janoshik and here's what the results showed: Main peak retention time:…

That reframing is the part I needed. Taking it to my next appointment.

Adding the clinical framing, because it changes how the question reads. 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.