This is exactly backwards. The impact of the neck and body woods is subtractive, not additive. In a way, it works in the same way the tone knob on the guitar works (if we can all stipulate that the tone knob on a guitar does, in fact, alter the tone of the guitar when manipulated). Bingo. If you put your tooth against the headstock of an unplugged guitar and pluck a string, you will feel the vibration through your tooth. This is a very simple, readily verifiable experiment. For anyone who wants "scientific proof", there you have it. You've just proven that some of the vibrations from the strings are dissipated into the neck and body of the guitar. The tone capacitor in a guitar bleeds certain frequencies to ground, which means that those frequencies are no longer present in the signal, which clearly alters the tone of the guitar. We know that any vibrations from the strings that are bled into the neck and body of the guitar are no longer present in the vibrations of the strings, which are being picked up by the guitar's pickups. How can this not alter the voice of the instrument? ...depending on the amount of torque applied to the screws, of course.