Brian: I don't think Tweekerman was talking about the Hologram things. He was talking about speakers. I think you are confusing Ben's (of Shakti) explaination of how the Hologram works--"like a speaker due to the amplitude of the wood he's using, which de-localizes the main speakers." That explaination is when the second speaker is active and has nothing to do with what Tweekerman is talking about. Tweekerman's tweak is not so strange. I speaker not hooked up acts as a bass trap capacitor, particularly if it's a sealed enclosure. It can work remarkably well for smoothing out the bass as it absorbs the low frequency and releases it slower and out of phase at a much lower volume than the original. There are some real tricks with placement here and you can actually tune the frequencies that are a problem.
Strangest Tweak?
Bricks atop amps, sandbads atop speakers,snake oil? And i am sure this is only the tip of the iceberg...