Shockhead, I agree with you
I think that the only reason that the wacky stuff you refered to crept in was that it was infererd that I had never heard of RFI. The reason I keep my power amp on the floor is 1 there ain't any room on the shelves and I don't need access to it as it is permananlly switched on. 2 to keep it away from my phono stage and cartridge etc because you can get hum big time there if your not carefull by electromagnetic radiation from the big transformer in the amp. In fact my phono stage is as close as I can get it to the arm there is no mains whatsoever within at least two feet of it (outboard PSU). That didn't cost any money though just a bit of thought.
Personally, I've not had any problems with the other stuff and it is all on shelves together like everybody elses.
When I think for the price of two of these exotic power cables I could buy a new state of the art autopilot for my boat including gyro stabilised course computer, hydraulic pump, control head, fluxgate compass, and rudder feedback, I'll happliy live without them.
Listen to the music mate, not the kit.