Unfortunately none of what JohnK has said is theory, it is solid physic/elctromecahnical laws, what we hear is in fact practice or theorectical as it can never really be proven nor disproven, since we all hear and like different things and it is a ll VERY subjective.
What I know is that if the wiring has an affect on the SQ when using the same amp/speakers/inputs etc. then you can be rest assured it is changing the sound from what it is supposed to be, whether that be bad or good is in the ear of the listener.
