Do speaker cables need a burn in period?

I would agree with you.  Like I said, what I said is just theoretical.  Whether you can here the difference is well ... it depends on your system.

Yeah, it's semantic.  I probably should have used the word "power".

It’s not semantic but that’s OK. As I said, it’s the wire not the electricity anyway.

"The rats went immediately to the door where the food had been the time before."

"He finally found that they could tell by the way the floor sounded when they ran over it."

There seems to be another variable that has been missed for the last 80 years. The one that made rats know in advance how the floor would sound when they ran over it. That may be what made them run immediately to the right door instead of tapping around searching for the right sound.

"When did arrows start appearing on audio cables?"

When someone needed a new, fancier, product to increase sales.