In my new "Le nozze di Figaro" score, the following passage is found in the aria "Voi che sapete" in bar 43:
In concrete terms, it is about the correct implementation of the appoggiatura - not, of course, from today's modern point of view, but from a historically informed one. So I read the chapter on appoggiaturas in Leopold Mozart's Violin School of 1756, and Mozart's father deals, among other things, with such appoggiaturas before dotted notes. He uses examples of sheet music to show how the notes are notated and then how they are to be played.
According to these instructions, you'd have to play this bar like this:
When I listen to this passage in different interpretations, practically all singers sing it wrong, as if it were a short grace note. They do not emphasize the appoggiatura, the effect of the dissonance resolution is lost. Harnoncourt also said, for example, that appoggiaturas should be longer and weigh more, and that would fit to L. Mozart´s way of playing it.
My question, however, would be whether anyone knows whether there were other variations at Mozart's time, how such a passage was to be played/sung. Is a grace note definately wrong here?