Please don’t misunderstand my comments- I am not saying that one should chose equipment based solely on measured performance. I agree, one must ultimately decide with one’s own ears. I am simply pointing out that specs, far from being useless, actually can add a great deal to making an intelligent choice that ultimately can lead to more subjective enjoyment.
Some will argue that certain measurements will indeed provide some indications on how something will sound- it has been shown by empirical studies that certain types of distortion is found to be pleasing to many, among other things. The success of amps with these types and patterns of distortion, typically certain types of tube amps, and ss amps that have been engineered to mimic these distortion profiles, are indeed successful in the marketplace. But so are others which take a different approach so while we can perhaps find certain sonic tendencies correlated to measurements, they are no guarantee of universal appeal.
It doesn’t make sense to chose solely on specs, nor solely on what we hear. It’s a thoughtful use of both that can be the most beneficial.