To re-cap or not to re-cap? That is the question

Mid40sguy--   I was being a bit facetious, but I guess the serious point was  that this is not step-wise?  (Perhaps someone can help me here).   I assume there is no difference between (1)  'break in' and  (2) 'aging' or 'degradation' (let's just talk tubes since no one doubts the aging process there).   It's just a slow degradation from the moment you turn them on until they wear out completely, with an (arbitrary?) period in the middle where we like them the best?   Not arguing here.  Just trying to figure out what happens.  Or are some arguing that once things get 'broken in', then they hit some steady-state of (perhaps finite) perfection?  

This comes up with all kinds of things,  just in my experience--physical books,  Mason jars, cars, sails, hair brushes, engines.    Is the process that electronic equipment is subject to different in any significant way?  (I would assume for some components it might be:  they either work perfectly or not at all, but in that case, there really is no 'break-in' period.).  Again, not arguing.  Just asking what audiophiles and electronics experts believe is happening.

All right, one final word, at least from me. And please: I promise I'm not trolling. 

I just got off the phone with the electrical engineer who repairs audio equipment in my community. I've worked with him for decades; he used to be the head of the tech team at the university where I teach before he started his private business as "The Audio Doctor." And, not irrelevantly, he describes himself as "a recovering audiophile." 

He insists that he has almost never seen capacitors fail, and that worrying about them "blowing up" and destroying the entire amp is plain silly. Active components like transistors, switches, and so forth constitute 95% of his repair work, he tells me. Moreover, he says that some electrolytic capacitors have "weep holes" that can leak electrolyte, and he has seen this problem (generally, the customer discovers some damage to the shelf on which the component with the leaking cap sits). Even with a capacitor that is leaking electrolyte, measurements will be within about 5% of what they should be. Furthermore, he says, circuits are very tolerant; most other components have normal functioning tolerances of 10% or higher. Bottom line: re-capping, he insists, will not improve my sound at all, nor am I risking a catastrophe from an old capacitor blowing up.

Now, I'm not saying he's right. But...I do trust him, he has 35 years of experience in the business of repairing audio equipment, and one would think he'd be motivated to suggest that I should replace my old capacitors, since I came to him wanting to do that, and he could have made money from me merely by agreeing to my wishes.

One more thing. My right speaker is more than 30 feet from my amp; the cable must go up and over a stone arch in my living room. The left speaker, however, is only a couple of feet from the amp. I've run 14 AWG copper wire--nothing special, that is--to both speakers, using the amount of wire I needed to reach the speaker. He insists this is completely fine, and gave me a long explanation of why I don't need to worry, which I'll spare you all. But I'm pretty sure just about everyone on this site will think I'm making a mistake not to buy expensive cable, and to run identical lengths of cable to both speakers.

Chances are, this thread is sleeping now. But it will be interesting to see if these remarks provoke a passionate response.

My passionate response is that it sounds reasonable to me...

I definitely recommend a re-cap, (my preamp is currently in the factory for that..) but preferably from someone who knows your specific equipment and the wide variety, cost and sound of available caps out there in that equipment. Cost does NOT necessarily correspond to what will sound best. When  you talk to the designer / tech doing the work, try to get an idea of what they think sounds good, what speakers they like, etc., so beyond their expert advice and experience, you have a sense of what they consider 'good sound'. Caps can to some degree tailor your sound... Some will promote ear fatigue in some systems, some are more laid back, etc...Caps are just one piece of a big puzzle.