[NotationUser]

I am not quite sure if the real answer is between both findings.

I think I remember there can be something in midi files that indeed represent cords on midi level as this can be used in arrangers like tyros to harmonize your voice for instance. But I am not sure if this is a proprietary feature probably just in XG or styles.

I don't own Midiland software but I know about it and it looks to be quite advanced when it comes to tweaking midi for entertainment purposes.