Does anyone use wood for vibration control?

Nope, same side. External vibration interferes with and distorts the electrical signal in wire. It does so whether the electrical signal is in the power cord, internal wiring, capacitors, transformers, speaker crossovers, speaker cables, interconnects, digital cable, what have you. As for the electrical signal in wire itself, it’s not (repeat not) vibrating. In an AC circuit it is alternating, but not vibrating. Follow?  What you hear from the speakers under normal conditions is relatively distorted - unless you’ve taken steps to reduce or eliminate external sources of vibration in the audio system by incorporating a comprehensive program of vibration isolation and damping. That’s what I mean when I say, the only good vibration is a dead vibration.

Nope. Not true. But it is funny. 😃 

So you think the physics books are incorrect, or I am incorrect in quoting them or both or what?

I don’t think you looked at physics books. I think you’re trying to define things to suit your purposes.