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
All of that makes no sense. The percentage of impurities is too small. If the copper is 6 nines pure, then the total impurities is only 0.000001. Tiny magnets, indeed. Give me a break! Plus even if the impurities did act like tiny diodes there’s nothing to support the idea they would all be pointed in the same direction. There would be more than just one.
He never said that all of the impurities would align the cable direction in one way over the other, but that it would/could create a conflict, of sorts (my words).

I’ve been told by a few cable makers that there’s no such thing as 6 nines pure anything when it comes to cables, so....

That, and when an argument is made that a tiny wire in a fuse can make a difference, who’s to say that small amounts of impurities that occur in crystal structure boundaries can’t have an effect? He never said it did, but that it could, which is why he's a fan of large crystal structures that one can achieve in an easier way with single, solid core wires as it eliminates, or minimizes, the possibilities. 

All the best,
Nonoise
Here's the one thing Skoff said that really matters:
 there's no way—other than by listening to it—to determine which direction a piece of wire's "preferred" direction of signal flow may be.


Exactly.
Actually for cables manufactured by Audioquest, Anti Cables, Goertz and perhaps others you can rely on the arrows 🔜 provided on the cables since those companies control directionality for those cables. In those cases you do not have to listen to the cables both ways. Obviously, for everything else you have to listen to the cables both ways. But seriously, who really does? Not too many!  It’s also why you can rely on the fact the Audioquest high end power cords will be in the correct direction when you plug them in. Because they are controlled for directionality. Ditto the AQ HDMI cables. 
Morrow cable do the same thing indicating with an arrow  ….I think they are serious...To verify...