when connected to a tough load not all amps sound the same.
Blumlein, your statement highlights the problem with many audio forum antagonists and trolls who appear to not understand the value of conditional statements.
Trolls, skeptics, critics and deniers, exist not only on audio forums, but at forums for many subjects, including those based on another major interest of mine - AGW/CC (anthropological global warming and related climate change). Complex and convoluted arguments, including mind-boggling Gish-gallops, are often employed to subvert obvious realities and often derail intelligent and productive discussions. The recent discussion here on "people are not measuring something that causes the obvious differences that I definitely hear in non-controlled, non-blind testing" appears to be to be a classic non-troll, Duning-Kruger situation rather than trolling.
True internet trolls are often very good at portraying themselves as victims of discrimination and abuse. while laughing at the rubes they sucked in. In their purest and most irritating styles, pure internet forum trolls are extraordinarily disruptive. Similarly, Duning-Kruger syndrome sufferers - who think they know something, but are totally wrong - often express the similar complaints of discrimination when their deficient arguments are disputed. Polite and whiny trolls and babblers can be difficult to deal with when they present themselves as victims of online bullying and abuse, because many of the intellectually honest participants are nice people who don't want to accidentally put-down someone who is possibly an innocent skeptic.
With reference to the above quote, of course not all "well-designed and manufactured" amplifiers with "no anomalies in their output" sound the same under all conditions, But if those two "conditions", it should be exceedingly rare for amplifiers to sound different driving "non-pathological" speakers. But trolls and disrupters ignore the essence of conditional statements, whether the conditions are implied or stated. Often this is a problem of ego (I'm right, and nothing will convince me otherwise), or perhaps they have a personality disorder that causes them to compulsively annoy and irritate others.
In an internet forum discussion, as it becomes obvious that a participant is either purposely trolling or just being pathologically stubborn in their unsupported stances, someone will call them out. Honest and "trying to be helpful" participants begin to realize that they are being played or dealing with unrealistic people who have no interest in reading the links provided and learning about the reality of the subject at hand (or they read the links and don't understand the information). Then the thread often degenerates until and unless a moderator steps in with their post-snipper or ban-hammer.
As a former audio forum moderator - nearly 20 years ago at three vacuum tube forums at AudioAsylum.com, I am acutely aware of the extreme difficulty of identifying a participants as a true troll, and the difficulty of encouraging lively and spirited conversation and discussion without having it degenerate and drive valued participants away.