I just looked a a few AMPLIFIERS and there is just normal THD shown.He tests one version of IMD (I prefer the twin tones at 18+19 khz), he doesn't test for DIM don't know I've seen anyone who regularly does. He does do a multitone which would show IMD even if not at the specific frequencies in the DIM test. He tests for FR, distortion at different levels and other things. The point being not that his tests are totally comprehensive, but that they are far more than a one shot one SINAD number and call it done. Yet you posted, "People keep saying that THD+N is all you need to know, because one sinus signal is sufficient." Like SIY, who says this? I only see people claiming other people saying this not anyone who does say this.
I saw a lot of people here say that THD+N is all you need, I don't need to provide a list, I am not at an congressional hearing.