That's an interesting approach Hollow.. I will give it a try when I get back to the studio later today. On the other hand, while thinking more about the advanced midi path today, it occurred to me that my second controller, the one 'always' playing both instruments, may have been set to midi global rather than midi channel 1. I'll first have to confirm that.
Going further down that path, it occurs to me that there might be a problem with using multiple combinators all using say, thor units for arguments sake. I'm wondering if all of the thors will respond to the midi signal or if only in the 'selected' combinator.
So many questions, so little time.