oh hey! I fired up my RSS reader for the first time in months and saw that Bob van der Poel released a new version of MMA: Musical Midi Accompaniment that includes a number of new fixes and features, including a patch I submitted last year that extracts groove information from a given .mma file.
I don't remember exactly why I even wanted this feature enough to implement it at the time, but it makes it a lot easier to consume metadata about MMA grooves.
I haven't tinkered with MMA much in a while; since getting my piano last summer, I find that midi backup sounds very wooden. But, I did dust it off the other day to make a piano backup track for practicing 'Tyro Mazurka'... and I think as a composition tool MMA could be very useful for algorithmically generating 'broad strokes' parts based on a chord progression; let MMA generate a midi file, import the midi file into Lilypond/MuseScore/etc, tweak, and engrave.