Just revisited this thread after a long time. There are many pseudo-science and even anti-science claims made by fancy cable makers. Stuff about skin effect, which is not significant at audio frequencies, polarizing shields, which is just silly, and other similar junk (like various metals, etc.).
When it comes to designing electronics, or electromechanical devices, it takes education AND experience. Each is not a substitute for the other, no matter the magnitude.
Regarding speaker cables:
1. Shielding isn’t necessary because the impedances are so low.
2. The lower resistance, the more damping factor is preserved.
Regarding amplifiers, the ideal voltage amplifier (as 99.99% of audio amps) has voltage gain and no output impedance, regardless of frequency, amplitude, or load. This is fact, and not debatable. If you’re an electrical engineer, this is something you were taught early in school, as soon as the core courses were out of the way, and simply second nature as a practicing engineer, if you are fortunate enough to be one. Some engineers get the degree and never wind up doing any actual engineering.
Now, we have speaker cables available, although we don’t push them or try to make any significant margin on them. They are designed for easy use (physically flexible) and LOW RESISTANCE! Our current top-of the-line model is the MEGA Snake, a 9-gauge equivalent cable! Here’s a photo....

Fact is, there are many companies, and individuals, that make up problems so they can “solve them”. This stuff comes from marketing, not engineering.