Yes... the very important point to remember is that even if we don't have any recording to really and objectively know how was a performance sounding, anyway we have a large literature of aneddocts and tales about the emotions and the "affetti" music was suscitating and expressing in both the players and the listeners.
But even more important , we have a large literature of treaties and theoretical or practical guideline for music interpretation, very precisely explaining several of the point littlewierdo was wondering about:
several rules were actually linking dynamics and articulations to melodic lines, and to the mood of the text, so the resulting performance of a line of music had "hidden" information for the musicians, and the habits/rules were so commonly accepted, that "being a good musician" was often measured by the amount of correct and universally accepted expressions and articulations you were able of implementing at first reading, beside the ability of introducing the expected, even if unwritten, diminutions (trills, embellishments etc.) to "finish" the music.
Actually some of the early music styles were so rich of emotions and expressions, that we have records of debates of thoerists about the "abuse" of expressions and dynamics, not the opposite.
Just a sterile and artificial misleading approach to ancient music caracteristic of the time from the early '900 to the '70s was pretty flat and unemotional. The modern school, after careful reading of the litterature is now going in the opposite dirction, just listen to music performed by modern specialists, and what you listen to is... MUSIC. In the real sense of the word. ;)