Rok2id,
As you seem to be one of those philosophers, I urge you to open the horse's mouth yourself.
Personally, I have heard the difference between cables on more than one occasion by experimenting, sometimes to my chagrin, once to my dismay. All kinds of materials carry current. Not all sound great doing it. If you were just worried about getting the signal from one end to the other, you'd use bare wire bought by the foot. I have seen speaker jumpers made of copper, silver, tinned brass, and aluminum alloy. I have replaced cheapo jumpers with cheapo wire with good effect in the past. I have had people in my apartment A/B-ing wire, and leave in a huff when their particular concoction got completely showed up by someone else's recipe, and I assure you the differences were not because of lack of ability of the lesser cable's ability to conduct electricity.
Otherwise, I think that the debate about how well wires carry signal is to some extent kind of silly before people know what two electrical loads/drivers are being connected with the wire. There isn't much we can do in a system full of wire... Tires is tires according to the "wire is wire" theory. But the best tires for my Ferrari are not the best tires for my 10yr old Pajero when I am rambo-ing around in the snow. Oops. Don't have a Ferrari. Well, if I did, they still wouldn't be the best for my 10yr old Pajero (which I do have).
