Interesting, Roger. However, given the numerous variables that one has to contend with in a system, like the type of speaker's paired with the amp, the room, the type of music preferred by the listener, the type of front end, the volume level that the listener prefers to listen at, the ancillary cabling and on and on; I do NOT see how anyone can really know for sure what their amp will sound like in the "typical" listener's system. Perform as to the measuring devices used, that's another discussion altogether!
I don't think that Vlad says he knows how his amp will sound in every system, every room, and with every different piece of equipment it will be lashed to. He certainly knows the performance envelope his amp is capable of when used with his preamps and partnered with appropriate speakers and the sound they are capable of creating.