Directional cables - what does that really mean?


Some (most) cables do sound differently depending on which end is connected to which component. It is asserted that the conductor grain orientation is determining the preferential current flow. That might well be, but in most (all) cases the audio signal is AC (electrons going back and forth in the cable), without a DC component to justify a directional flow. Wouldn't that mean that in the 1st order, a phase change should give the same effect as a cable flip?

I'm curious whether there is a different view on this that I have not considered yet.
cbozdog
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The signal travels in one direction down the wire >>>>>>> from the source to the load. It is NOT alternating back and forth.
The signal, energy, travels down the wire in the form of an electromagnetic wave from the source >>>>>> to the load. It is not alternating back and from the source to the load. > < > < > < > .
I understand what you’re saying, but energy flow only explains part of the equation. The other part is what in the actual metal structure that affects the flow of energy in one direction vs the other.  I mean what in the metal structure that favors the direction of energy flow.  I am still looking for a scientific explanation why in one direction, energy flow is better vs. the other.
If higher metal purity results in better sound, then Skoff’s imaginings show some merit. The differences can be small but the end product is a more enjoyable one, and to some, it’s worth it to pursue and make.
I understand. It’s like in the court of laws, there are a lot of circumstantial evidences but I am still looking for the so called "smoking gun".

For example, lets say you have a diode.  You connect a sine wave source on one end, and measure the output on the other end.  Then you connect the same sine wave source on the other end and measure on this end.  The output should be the same.  But of course its more complicated because you have a lot of these small diodes in the metal structure, not ONE diode.  So I am looking for some "hard" explanation why these diodes would make a difference.
Anyway, since this forum does not allow posting picture or images so it's hard to discuss anything technical here, I created a thread over at DiyAudio.com and make an attempt, albeit a bit primitive and you could say "simple minded", to understand cable directionality.  But that's all I got lols.

https://www.diyaudio.com/forums/the-lounge/340158-symmetric-circuit-difficult-question.html#post5850083
Question - If there are a “lot of tiny diodes” in the wire as you suggest how do you explain why they would all be in the same direction? Furthermore a diode inherently suggests the signal is transmitted primarily in one direction. But this is not the case for wire, even when the wire is described as directional. In the ordinary world, the one outside of audio, the word directionality has no meaning. It’s strictly an audiophile term.