Erudite, detailed and accurate.
However, it misses slightly my basic point.
If we are spending massively over the odds (and we are) on 'serious' hi-fi products, why the fuck are we putting up with design and build that is incapable of dealing with mains-borne interference and voltage shifts that are inherent in virtually every mains supply in the land?
If I can buy an amp for £100 to run my guitar through for gigging, and it shoves out a decent 500Wrms and suffers NO effects from mains interference, then why should I accept that a £5000 hi-fi power amp should need me to spend a further couple of thousand pounds on power conditioning in order to be usable in normal domestic situations.
No fucking wonder the domestic audio market is in such a mess. 'Fitness for purpose' comes to mind...