As cryneanaudioriver pointed out: you really left science and engineering behind in your post because you have simply assumed (e.g. in the case of your Shunyata cable) that your perception is SO reliable that you just CAN’T be wrong, and that therefore if no technical theory or measurement can validate "What You Hear" then it MUST be tests that are wrong, not...ever....you!
THAT is the fundamental problem underlying most of the subjectivist/objectivist debate. The Utter Certainty many have in their own perception...which flies in the face of all we know and has been studied about the fallibility and liabilities of human bias and perception.
It seems either a case of flat out refusal to learn this due to maybe some ego-protection mechanism, because people wrongly feel they are being personally insulted if it’s dare suggested they are "hearing things." Or it’s a case of some people just not-knowing-what-they-don’t-know and so they just won’t accept any informed testimony that contradicts their self belief.
Which is too bad.
My son was involved in a large study for a peanut allergy treatment. It was double-blinded - neither we nor the researchers knew who was on the actual treatment or the placebo. This is STANDARD in such trials because of the well known influence of bias - people who know they are getting the treatment will often report it made them better (even if it didn’t) and visa versa. Wouldn’t it be strange for my son to have objected "How dare you insult me by suggesting I may be prone to imagining anything! I demand that you unblind this study. I can trust myself, why can’t you?"
That would just be a flat out misunderstanding of the nature of human bias, right?
And yet this is pretty much what one sees among many here: a flat rejection of the proposition they may actually be imagining differences, and a rejection of any way of coming to that conclusion. It’s a one way street: I KNOW I hear the difference, so the only answer I’m looking for is one that affirms that belief!
As I mentioned earlier: I also felt very strongly I heard an "obvious" difference with a Shunyata cable in my system. But I was open to the possibility of listener bias as well. So I did a blind shoot out and when I didn't know which cable was which, there was NO detectable difference - my guesses were completely random.
Saved me a lot of money :-)
It's too bad more audiophiles haven't had such experiences. It's an eye-opener.