Burn-in question

That's a stretch. Besides, the Cable Cooker customers have no financial interest in making that observation.  Don't be such a conspiracy theorist.

The manufacturer and owners of the high end burn in device Cable Cooker by Kafton actually report that re-burning cables in say, once a year is effective, so one might reasonably conclude that yes, burn-in is not permanent. Not to mention the conclusion that playing music through cables is not as effective as more stringent methods.