A comprehensive write-up. Nice one!
Did I notice a bit of “mains cables can/do make a difference” creeping in, because as you well know they CANNOT . So you, me and everyone in the Audioquest room was either fooled or deluded (not forgetting, suffering from expectation bias). Did you get to hear those enormous AQ mains cables?
Audioquest have previously been caught:
https://www.audioholics.com/editorials/mark-waldrep-audioquest-open-letter-editorial