The 2nd part of the post you quoted has nothing to do with cables. It's just explaining how electromechanical feedback works in an audio system, so you can understand WHY we want to preserve as much resolution as possible.
IC cables make a large difference in resolution, they can preserve the information or smooth it over because of added colorations like warmth. They do little to participate in feedback, except produce triboelectric noise as a result of friction between the conductor and dielectric, which is not desirable, but also nowhere near the effect of a vacuum tube or a turntable.
I did explain what I meant by good and bad vibrations. Good vibrations lead to psychoacoustically correct feedback and bad ones do not. So when we test the effects of racks, footers, tube dampers, turntable platters and mats, adding weights, etc. all this is manipulating the electromechanical feedback mechanism of the system in order to make it psychoacoustically correct.
I also said that the result of good vibrations that create psychoacoustically correct feedback is the perception of timbre sounding more like it does in real life.
For example, the vocals I heard with the resonator in the horn (as detailed in the post you quoted) sounded clearer and more real, without it there was a dullness to the sound, and it sounded less like I'd expect vocals to sound like in real life. At the time of that particular trial, I was expecting the resonator to simply add coloration and take away from the reality of the vocals, but the result was quite surprising. The vocals sounded clearer and more real with the resonator! I forget the brand, but there have been several different products that attempt to store the speaker's energy and release it over time in order to enhance the reverb trails and make the sound more realistic. I have heard it really work, but I also think there is a possibility the resonator would result in additions that are not like we expect to hear, which would then make the sound seem more muddled.
In any case, if the goal is a 3-D immersive "you are there" soundstage, then commodity level IC cables will be a bottleneck, and psychoacoustically correct electromechanical feedback helps. We've already gone over the fact that recording and playback are not the same thing. Recording is an art, or at least a high-level craft, reproduction is simply retrieval of the recorded information. Both sides of the equation can be good or bad. The goal of playback is achieving the most fidelity to the recording as we can, hence the term "high fidelity", which has been maligned by those who are ignorant of these facts or have been exposed to HiFi systems they don't enjoy and feel are flawed. The thought that what's used to make the recording is "good enough" for playback shows a fundamental misunderstanding of the differences between the two endeavors.
Ok.