The "most foolish" loudspeaker tweak/upgrade ... is

ptss, that explanation adds much to the discussion; thank you!

@fliz That being true, is it regulated by price? All things being equal (materials, configuration, etc) at what price point do you reach diminishing return? Does this mean the more expensive the produce, the better?

(Caveat: these questions overlook the actions of your typical audiophile with a large budget.)

The concept of twisted pair is nothing new, it's been known sonce the days of the telegraph, I.e., number of twists per inch depending on the frequency or gauss of the magnetic field or EMF. Basic stuff I learned in college all those years ago. Audio cable makers didn't invent this idea or discover it. it certainly doesn't add any cost to making cables. 

@alpha_gt So what of the $39k price tag for cables?

From our friend Wikipedia,

"Twisted pair cabling is a type of wiring in which two conductors of a single circuit are twisted together for the purposes of canceling out electromagnetic interference (EMI) from external sources; for instance, electromagnetic radiation from unshielded twisted pair (UTP) cables, and crosstalk between neighboring pairs. It was invented by Alexander Graham Bell.[1]"

My note: twisted pair cancels RFI/EMI, but not magnetic fields. Magnetism is a horse of a different color. Shielding, absorbing, rejecting, cancelling magnetic fields calls for something a little more uh, stringent.