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

ptss
30K for wire. They should quite using chip board  boxes, that might be worth a few $$$

FWIW, I dont really care how mucfh a person spends on speaker wire, which seems to be the  most answers, to the OP's question, so I'll give my humble opinion. I would totally forgo any cable upgrade until my ROOM was at its absolute best configuration, I.E treated for sound. Thats also a very inexpensive fix to improve on any, and I mean any speakers performance in a given room. After that I would obtain the least expensive, reputable cable i could afford and I will venture to say that a relatively reasonable priced cable will really satisfy. Of course if you have unlimited resourches go for it.

Alpha gt - You have put into words the most logical explanation of wires i have ever seen on a forum . "Ideal would be no wires between components and no wire can add something that is not there to begin with"    Perfect statements !

Alpha gt,  IMHO you are correct.  'To each his own':  I would only add that, as members of the human race with our foibles and our sense of humour, we will make fun of silliness whenever we can.  For my own part if I ever bought such cables I would expect to be laughed at.

"Ideal would be no wires between components and no wire can add something that is not there to begin with"

This theory can be tested, the Digital Audio Company makes monoblocks called "In Line Maraschino amps", that are so small & light they can be hung off the back of a speaker at the binding posts with just a couple of inches of wire. Compare the sound of them hanging off the posts and then connect an 8' pair of cables, is there a difference?