Why Power Cables Affect Sound

I just bought a new CD player and was underwhelmed with it compared to my cheaper, lower quality CD player. That’s when it hit me that my cheaper CD player is using an upgraded power cable. When I put an upgraded power cable on my new CD player, the sound was instantly transformed: the treble was tamed, the music was more dynamic and lifelike, and overall more musical. 

This got me thinking as to how in the world a power cable can affect sound. I want to hear all of your ideas. Here’s one of my ideas:

I have heard from many sources that a good power cable is made of multiple gauge conductors from large gauge to small gauge. The electrons in a power cable are like a train with each electron acting as a train car. When a treble note is played, for example, the small gauge wires can react quickly because that “train” has much less mass than a large gauge conductor. If you only had one large gauge conductor, you would need to accelerate a very large train for a small, quick treble note, and this leads to poor dynamics. A similar analogy might be water in a pipe. A small pipe can react much quicker to higher frequencies than a large pipe due to the decreased mass/momentum of the water in the pipe. 

That’s one of my ideas. Now I want to hear your thoughts and have a general discussion of why power cables matter. 

If you don’t think power cables matter at all, please refrain from derailing the conversation with antagonism. There a time and place for that but not in this thread please. 
Straight ahead.. polished conductors means the company polishes the wire before they are put into shielding. No brainer. Polishing them makes they conduct more evenly.. better... smoother.. At least that is the idea. I would also think they are polished in a non- oxygen atmosphere..
I polish my AC plug blades...
Perfectly valid question re highly polished conductors. Here’s what Audioquest says, this paragraph refers to their Dragon High Current Power Cord.

HIGH PURITY CONDUCTORS - PERFECT-SURFACE SILVER (PSS)Perfect-Surface Technology applied to extreme-purity silver provides unprecedented clarity and dynamic contrast. Perfect-Surface Silver (PSS) is AudioQuest’s highest-quality metal. Solid conductors prevent strand interaction, a major source of cable distortion. Extremely high-purity Perfect-Surface Silver minimizes distortion caused by the grain boundaries that exist within any metal conductor, nearly eliminating harshness and greatly increasing clarity compared to OFHC, OCC, 8N and other coppers.

Lizzie, you said you thought they were polished in a non oxygen atmosphere. Do you mean like on Pluto?
No, I mean a pure nitrogen atmosphere. Like a Taco Bell restroom.
Roger of Ramtubes has the opposite view of Atmasphere and myself.  He says that any PC cable that sells for over $100 is a waste of money.  He thinks that there are advantages to better quality PCs but not after $100 price.  I've tried maybe 20 PCs in my time, including lower and middle end Audioquest, Magnan cable (horrible High Fidelity cable), etc. and found GroverHuffman cable to outperform them at $400 to $900 (depending on model).  Very much higher than $100.  Infinitely more complex in design than a $100 cable as well.
1) Only poorly designed gear benefits from upgraded power supply cables or power source (power conditioner, etc.). If your product benefits from it, return it and get a better made one.
2) Unless you are doing a long run, EMI is not an issue unless you literally have a radio tower next to you. Even then, a well shielded cable or a ferrite chocker can be very cheap, no need to buy >$100 cables. 
3) Mains noise is also usually isn’t that bad, so fixing it likely wouldn’t provide much of an audible difference outside of subjective opinions.