Is your post supposed to make sense? Because it doesn't.
What is an "infinitely varying load" exactly?
What are current deficiencies? Is that different from clipping somehow?
And your analogy is, well, a stretch, a reach, to put it politely.
And when did I say all amps sound the same? A more careful reading of this thread would tell you that I took his word that his two amps didn't sound the same. I've done blind tests and found amps that did not sound the same. But that's not the point. The point is that when they don't, there's a real reason for it, a technical explanation in there somewhere. And I'm fully well aware that THD is but one of those possible reasons. I test consumer audio equipment for a living. THD, linearity, freq resp, SNR, IMD, source impedance, etc, etc....
For every new thing I learn, I forget two things I used to know.