The perception point is a valid proposition but opens the door to all sorts of things like the neck and lyre screw by Ishimori or the immortal P.Ligging or the metal hook to your strap or the superstition about one finish over another or the infamous cryogenics.
The argument used is that despite the inaudibility in an experiment of the influence of the attribute in question the player hears it or thinks he hears it, therefore is positively influenced and therefore he plays better.
Nobody thinks of implementing a world saxophone police going around and checking that you don't use any of these or whatever else you want to use in the belief that it improves your performance. The point is an entire other.
The maker of an implement sold or not ( the P ligging or the metal hook costed nothing or were already part of something bought by the player for another purpose), his friends (!) or his fans come here to a discussion forum to discuss the merits of a certain thing, but then the moment they are questioned about showing the beef, all they can say is, it works for me therefore it is so. I can feel it, I can hear it. You can't, it is your problem.
They come here or elsewhere with pseudoscientific claims looking for validation in a discussion, but then refuse the same science that they claim is at the base of their magic amulet. Which is, if you ask me the same as throwing the stone and hiding the hand!
Claims are made, often of a pseudoscientific nature ( it improves vibration transmission, it changes the crystalline structure.........) and then they say well, we can't prove it in a controlled experiment, but we don't need to, it works for me, so, deal with it! Which equals to the teapot proposition.
I sayn the teapot is there, I can see it, although we cannot prove it is there it is there nonetheless. The teapot (or rather its representative on Earth, the amulet) has changed my playing, therefore it exists.
If they would sell it as a magic amulet I would have nothing to say about it! It is the false pretense of science that is my problem with these things. One cannot be and stay believable first claiming Science to support the use of an object and then, when science cannot be proved, say science doesn't matter because this is art and the artist doesn't deal with science! So why claiming science in the first place?
I know of countless people, in the arts or not, who follow all sorts of magic rituals and trust many amulets to do this that or the other for them.
Despite my pretended rationalism I have these things too, it is human. I have studied plenty of Anthropology, Ethnology, Sociology and History of Religions in my young years at Uni and my academic world was full of rituals and amulets.
There is something called Apotropaic magic which as been present with mankind since time immemorial. It is the belief that with a formula or an object one can ward off bad things and improve the world around oneself. This seems to be a deep need of the humans to get solace, trust and courage through the use of some object or the performing of a ritual.
Do I tell people not to draw an eye on the bow of their ship because that is not going to change the weather, their luck, ward off the evil eye or get better catch for fishermen?
No I don't.
But do I tell a person telling (and selling!) that a piece of metal that he claims it changes the sound ( but cannot prove it does) that the supposed science is not supporting the sound change? I do!
You are of course free to use any amulets you want, but I am free to say they are just that!