Just to reinforce the caveat emptor warnings, this is the spectrum I get when I 'push' the Yamaha (a pretty good forte+):
I still see the energy spread fairly evenly across the first 5 harmonics, which seems to be a fingerprint of how the Yamaha plays me. But the cautions are correct. It's very easy to jump to unwarranted conclusions.
I think there's pretty solid agreement here that there is a big difference between measurements taken of the equipment in isolation, and a more holistic approach that looks at the performance of instrument and performer combined. While the first is sort of interesting at an academic level, I'm a fair bit more interested in what's going on when it's me playing them, in the way that I play them (or that they play me). This is of necessity highly subjective, and most definitely will not give a "trumpet X is better than trumpet Y" result. But seeing how different people can get different results on the same basic equipment set up is interesting in itself, isn't it? And maybe of more practical significance to us as performers rather than amateur physicists