There is nothing sarcastic in my subjective remarks. I routinely perceive differences that would not be real in any kind of controlled test. Such differences for example occur because you forget how the first sample really sounded like. And once bias sets in, the first sample continues to sound worse. Track content also changes over time. As does your listening acuity. Importantly, such tests need to be repeated many times to rule out variations.
Bottom line, just like any subjective reviewer/tester, I perceived differences. My brain concluded things that are not possible based on measurements and what we know about the science and engineering of said cable(s). I truthfully reported those so that people who are in the other camp don't think we deny what they think they "hear." We hear it as well as they do. Difference is that we know the difference is not durable, or reliable.
The sarcasm remark was not intended for you, but for many members here who must have sucked all the knowledge and wisdom of this world.... based on the sheer volume and severity of their comments here on these forums, making the environment unpleasant, which is a real shame because I do appreciate the overall content a lot. Not only from you, but from other members who share their tests so willingly, asking for nothing in return.
In the case of USB cables, you performed the tests that quickly have shown there's no difference. The fuel for those who thrive on sarcasm and bullying was provided at next to nothing of a cost.
At the same time, you were able (despite what you are now saying) to clearly hear the difference, which was obvious after performing the listening tests repeatedly.
The bottom line
is that you are given the opportunity to create the test environment and create & perform the appropriate set of tests, which will clearly explain what hearing/listening subjective tests are showing, repeatedly.
Re: USB cables, you performed the test that is applicable to... maybe 10% of actual applications. You used a DAC with a galvanically embedded USB card. E.g. the USB card ground fill and the DAC ground fill are sitting on the same potential.
The USB cable will play an infinitely more important task, if you choose a DAC with its USB card (module) that is galvanically isolated from the DAC These DACs are usually much more expensive than the one you used for testing, and the USB cables in question would sound vastly different. Would they measure differently? They SHOULD, in this case... ESPECIALLY at 1024DSD / 1.536MHz rates.
If they don't (measure differently) => the measuring equipment test jig is not used in the appropriate user case/scenario, AND the test-sets are of insufficient ability to capture what we humans can hear.