... what is Settling Time in cables and interconnects...

Hi

Always find these discussions interesting. This is an obvious, but effective demonstration of what resides in the "air" around us. 

Consider how low the signals are that make the sound happen that we all enjoy. Then take into consideration the amount of electrical noise that is currently being generated by all of the local "things" in our homes as well as all the signals being pumped through our environment. It seems only reasonable that the question posed by the OP is in fact, relevant.

Enjoy this simple little video...

https://www.youtube.com/watch?v=E4CQTgDfDmo&vl=en

In my opinion, I don't buy into everything mentioned in the above posted video. Many with degrees and/or highly educated in electronics are quick to judge a concept and say it can't happen, however, they don't attempt to explain why the listener can hear a difference other than saying it's your mind or ears fooling one's self.
I'll believe what I hear over theory every time, and I won't have a scientific theory to prove when I hear.

“What’s in the air,” cable settling time and cable burn in time are what we call INDEPENDENT VARIABLES. They must be considered individually independent of the others. And they are not the only variables involved, either.

no one is questioning your interest in the topic, simply that there are many many threads, even very recent ones, that cover this endlessly

my cables are recommended for a few hundred hours break in and a week settling