I want to start a discussion about this and maybe get a change into LilyPond.
Currently, you can get an "impossible (de)crescendo" error in LilyPond if your crescendo has a \sf in the middle [1]. It stops the crescendo and if you restart it, ending in any dynamic mark, you get an error. This is because a \sf has a MIDI volume of 100% and this volume continues afterward.
My understanding of a sforzando is that it is an accent. So my feeling is that it shouldn't act like a dynamic marking. The MIDI volume of 100% is fine for the note this marking is on, but then the volume should go back to where it was before the sforzando and the crescendo should continue.
Thoughts? Comments?
% [1] %%%%%%%%%%%%%%%%%%%%%%%
\version "2.18.2"
\score {
\relative c' {
c4 \p \cresc d e f |
g a b c |
d \sf \cresc c b a |
g f e d \f |
c1
}
\layout {
}
\midi {
\tempo 4 = 140
}
}