Let’s clear up one thing. The accusation of hype and unsubstantiated claims is a common pseudo skeptic ploy but be aware there’s actually nothing wrong with marketing one’s product, even using hyperbole or what Judge Judy refers to as puffing. You know, like World’s Best Coffee. Or, "you will hear things in your records you never realized were there."
Audio manufacturers, perhaps in particular tweak manufacturers, are under NO OBLIGATION to reveal measurements or method of operation or prove the operation of their products. That they are under any such obligation is an old wives’ tale perpetrated by naysayers and pseudo skeptics who employ that tactic all the time as if it means something, like bringing up controlled bind tests as if some device or tweak under would be proven a hoax if it were subjected to controlled blind tests.
Getting back to reality, the manufacturer might not know how his particular product works. Or he may wish to keep the information under his vest. In fact, as I just pointed out earlier, HiFi Tuning admits perhaps even a little sheepishly 🐑 🐑 on their web site that measured data of fuses doesn’t really completely explain the relatively large differences heard in listening tests. Hel-loo! But at least they tried. You know, unlike pseudo skeptics.