I tried something like that although not about power cords. It was boring.
In any case, difference was, if anything, small. In those moments we felt there was a difference, it was unclear if it was for better or worse. Waste of time.
If you need to do the test, the difference is negligible.
If, in a relatively decent system, your jaw drops with some cord change, or similar minor maneuvre, you'd better enjoy it as long as you can. The magic will go away with next cord available.
If you think it was not a minor maneuvre, you just learned you are very impressionable.
In any case, difference was, if anything, small. In those moments we felt there was a difference, it was unclear if it was for better or worse. Waste of time.
If you need to do the test, the difference is negligible.
If, in a relatively decent system, your jaw drops with some cord change, or similar minor maneuvre, you'd better enjoy it as long as you can. The magic will go away with next cord available.
If you think it was not a minor maneuvre, you just learned you are very impressionable.