As a long time audiophile, I feel like I've seen more than my share of "honest to goodness real tweaks that will be around forever" come and go.
Remember Peter Belt and his tin foil and alligator clip tweaks?
How about quarter sized Harmonix discs that, when placed in a large room, "totally affected the sound" to a greater extent than moving furniture ever could.
How about those disc things that we were supposed to roll along our baseboards to focus imaging.
Green pens for CD's.
Armour All on CD's.
Green-light bathed cables.
I bet y'all can think of more than I can.
I can recall a time when almost all of these had a reviewer or reviewers by the short hairs as he proclaimed their "reality."
After a while, they aren't mentioned any more and I never see them listed when a reviewer describes future reference systems.
I'd love to see these things revisited and kept as part of the lexicon of our hobby. Maybe we could maintain an index of all these "real and true" interventions that have risen and fallen from fashion.