I've always thought that articulation defined a player as much (or more, sometimes) than the tone quaility alone. Raphael Mendez comes to mind first. I think if we could take recordings and fade into a long tone without hearing the attack, it would be much more difficult to tell anyone apart, especially if the notes were at about the same range and volume. In orchestral recordings, I've sometimes head a note fade in softly and it can be hard to even identify the instrument until the articulation gives it away. Most trumpet players I've known who were obsessed with their "sound" end up sounding artificial and forced, whereas most people who have a very distinctive sound, are distinctive because they just play as themselves.