You can do a send from a midi track to a physical midi device, but midi send would be more useful if you could do a midi send to midi track.
I agree, you could use 1 midi track to control some parameters of a group of midi tracks. For instance, in Spitfire Strings (whichever) you could control the mics of all your strings with only one midi track and then having individual midi tracks per each instruments for notes and individual CCs.