I'll go the other direction....the best tweaks are a good glass of scotch, a poke of herbal essence and the wonderful cover of night. System always sounds great under these conditions.
What’s your vote for the most ridiculous, overpriced, and useless tweak?
My vote: Furutech Outlet Cover 105 NCF $220, with “special crystalline material that has two “active” properties.” https://www.thecableco.com/outlet-cover-105-ncf.html