"quite possible that the human ear might be on some level analyzing things that are either yet to be identified and labeled"
Transient Intermodulation, unknown until 70s, comes to mind. Early SS amps sounded very bright because of overuse of negative feedback but designers claimed that it has to sound better than tube gear since THD and IMD are way lower. TIM is very seldom tested since there is no established test method. Even the simpliest specifications like THD don't show the full picture since it is different at different frequencies and power levels.
As for being able to repeat particular amp, I'm afraid that no matter what you do SS won't sound like tube gear simply because of completely different interaction with the speaker. SS amps are voltage sources while tube amps are power sources. You can attempt to emulate sound of particular amp/speaker combination in DSP processing (many guitar amps do it) but results are rather poor. Nobody, so far, was able to make electric piano sound like real one - not even close. We are pretty much on the level of trying to understand why wires have particular sound (silver vs. copper etc.). Even same tubes made by different manufacturers sound different. It is still mix of science and art.
Transient Intermodulation, unknown until 70s, comes to mind. Early SS amps sounded very bright because of overuse of negative feedback but designers claimed that it has to sound better than tube gear since THD and IMD are way lower. TIM is very seldom tested since there is no established test method. Even the simpliest specifications like THD don't show the full picture since it is different at different frequencies and power levels.
As for being able to repeat particular amp, I'm afraid that no matter what you do SS won't sound like tube gear simply because of completely different interaction with the speaker. SS amps are voltage sources while tube amps are power sources. You can attempt to emulate sound of particular amp/speaker combination in DSP processing (many guitar amps do it) but results are rather poor. Nobody, so far, was able to make electric piano sound like real one - not even close. We are pretty much on the level of trying to understand why wires have particular sound (silver vs. copper etc.). Even same tubes made by different manufacturers sound different. It is still mix of science and art.