Perhaps the "science" (???) may work more precisely on raw brass instruments, but then I'm thinking if so, it should also work like a piano as when struck with the head of a key note on the tuned string. Otherwise, you wouldn't need a violin bow whereas I'd use a rosined edge of a light piece of balsa wood. Really, I've seen a country fiddler playing using a piece of rosined wood (what kind unknwn to me) in lieu of a horsehair strung violin bow (Disclaimer: Such was not my Grandfather who also played a country fiddle). I still stick to my variable theory.