Not sure what tip you want Matt. Its simplicity itself ro achieve what the OP wants in RB. BIAB is a little more complicated but clearly described above. Once a file is open in RB users still have access to adding RTs, regenerating, multiriffs and editing midi tracks so I always prefer to go straight to RB. If you want to work on a midi file maybe there are some advantages working in BIAB - I think Jim or Charlie posted reasons that BIAB could do things RB can't - but for what the OP wanted RB is the simple solution.

Does anyone know what happens if you open a midi file in RB then save as BIAB file? Do the separate tracks import into BIAB easily and simply? If so, surely that's the easiest way to import midi files onto separate tracks.