How much does volume matter when breaking in amps and cables?

Phomchick: You obviously didn’t read my first post in this thread - equipment “break-in” has nothing to do with returns.

geoffkait: What kind of rooms are you visiting at these shows?  Manufacturers absolutely have control over who they partner with - excuse me, REAL manufacturers!  Maybe the hobby guys struggle with who to work with?  

aberyclark is correct: Models of equipment brought to the shows to play are current production pieces.  

And geoffkait, we are coordinated enough to contact other companies we like to partner with to get equipment we need for the shows, unless we already own it.  

So with that, I also have to ask - how are you drawing these conclusions and where are you getting your info from?

What would you measure? 

millercarbon there is a huge difference between mechanical devices and electronic devices. Undoubtedly, electronic equipment drifts slowly overtime as some component values shift with recurrent heat cycles although I have never seen objective evidence of this. There is no electronic device that I know of that changes its characteristics in the first several hours of usage. Imagine what that would do to computers! Certainly tubes need to warm up and stabilize. Maybe class A or highly biased AB amps sound a little different after they heat up although having had several class A amps I have never been able to hear this and again have not seen any objective evidence of this. People come up with a bunch of fuzzy theories why electronics and wires need to break in. All of them conjecture, mythology. I can say that all the full range ESLs I have dealt with do require a period of loosening up. Their diaphragms are tightened up with a heat gun after they are mounted and they do relax over time. This only effects the very low end. Perhaps some dynamic woofers may improve with break in as you can imagine their spiders and surround loosening up a bit with use. But again I have never seen any objective evidence of this. 
I own two 911s a 2006 Speed Yellow C4S and a 2014 Guards Red Turbo S. Porsche's break in recommendation has always been "keep it under 4000 rpm for the first 2000 miles." Absolute torture but there is no substitute. 

Geoffkait, I would measure input and output impedances along with distortion values and rise time. But if there was no change the mythologists would just say the wrong stuff was measured. I would love to get a serum porcelain level on them.