Kim Patrick Clow:

>Sussmayer's completion is full of musical blunders.  Even Mozart called
>him an idiot while he was alive, and judging from other pieces of music
>he wrote, he was pretty much a hack.

It's also full of musical felicities, such as the Benedictus and
the Agnus Dei.  You know, I keep hearing about these blunders, and the
ones that keep getting brought up are simply departures from statistical
norms.  As for the other pieces, I agree, but I would say that lightning
struck at least once.  Furthermore, Mozart's widow was the one who
denigrated Suessmayr, as part of her marketing strategy.  I wouldn't
trust anything she said.  She also, if I recall correctly, destroyed
all the original sketches to hinder discovery as to who composed what.

>There are some studies that indicate that the themes from the portions
>that Sussmayer completed are Mozart.  These could be based on the missing
>sketches that Mozart's widow mentioned.

Actually, scholars (don't ask me how) have determined who worked on what
movements.  This is reflected in the Baerenreiter edition of the score.

Steve Schwartz