It’s been a while and I just re-read this thread, probably dead now.
However I have recently done some wiring in my amplifier and found this thread about helix wire geometry. Yes, I used the helix wire geometry with Cat 5E wire.
I used to make Curious Cables in Australia, and without giving too much away (or maybe I am?) annealed silver in PTFE tubing with quite a bit of space for air, and USAF wire used in fighter planes was purchased through a wire broker. There is a woven pair of grounds that go around the signal wires, not dissimilar to the same concept as the helix.
There may be others that can beat Curious Cables USB, but are there any that can for the price?