Totally agree with we do not know what or how to measure sound differences in certain cases.
I remember when CD players first came out and most everyone said they'll all sound the same. Yet when I audition several, it was clear most sounded different and a few sounded much better then others. I was told BS - you can't tell the difference. But I could. The issue was, no one had the understanding of what to measure. When they finally did (Jitter, etc.) then those disbelievers changed their tune. Oh you can measure it? Then it must be real now and I can hear it too.
My point, some of us can hear the difference between speaker wires, cables, fues, etc. some can't. I can tell the difference between zip cord and my Audience speaker wire. I cannot tell the different between power cables, but I have upgraded them from the thin, free, black ones. You can call me names for not hearing the difference and still buying them, but one day we'll be able to measure why they and other tweeks sound different and then all these na-sayers will jump on the bandwagon also.
Oh, it can be measured? Then it must be real now, wasn't real before..."