Yes I think so, just have the .mid and .SGU
you could have it in the SGU it's self like the RealDrumCharts are in the Melody track.
OR further you could have a RealMidiStyle UserTracks where you have all your midi tracks in the BB tracks in the SGU with all the recorded material with lots of chords and variations, rather than how the normal midi styles are based on the C7.
So if there is no associated .mid with the .SGU it will use the BB midi tracks in the SGU into 1 multitrack midi.