Everything matter in the audio chain. Tests prove it!

From the article:

Do cables affect frequency response? Yes. That too is visible and measurable. In particular, the Shunyata deviates in a positive way. And this cable does so in all cases. Your author believes that it has been proven that a cable has an influence. In our tests it is about values of sometimes 0.5 dBu. That is audible. Is it worth a serious investment? We’ll leave that up to you.

the differences will be notably more huge, if one does transient and complex transients stacked and their harmonics, as a fundamental test.

As LITERALLY, that is how the ear hears and works. the other 90% of the signal used in the test, is meaningless, as the ear never uses and never hears it.

This is about how engineering and tests relates directly to how we hear. So get it right.

Getting closer...

OP,

Yes this is interesting and potentially of some value in choosing or tuning a system. The more tools the better.

Yes everything matters including the individual. 

If you have a high-end projector in your stereo/video room, try an audiophile power cable. I recently experimented with a SOTA power cable from Audio Magic replacing the stock cable and the improvement in picture quality was dramatic. I guess everything does matter! 

Everything matters even more if it isn't plugged in. Yah, some of my customers were concerned about a unit that I sold many of, not working. To cut to the chase, I quit putting the power button on the rear of the unit just for that reason.

  Of course everything counts, it is just a matter of to what degree. One exception would be that if a cable or component had an issue in the first place and you replace it with something working properly, then no doubt you will hear an improvement. 

 That is a coarse way of stating that everything does matter but to varying degrees.