Glad to know I was on the money, or rather that my experience was reproducible and not some odd behavior here, because you might understand how what I suggested might have sounded at first! It’s one of those cases where it’s so simple it just seems impossible to be true. As I said, either our friends left some loose ends, or some wires got crossed in the process.
I hope we get a native way to manage MIDI connections soon. I’ve been using Max to manually make sure there is no loopback. I’ve blacklisted only the virtual ports Max creates when it’s running, and I just send everything there. Haven’t bothered to setup a whole orchestra outside while Dorico is talking to the DAW because, as of yet, it still feels like a trudge.
And if we could get ReWire anytime soon, even if just to sync transports… italian hand kissing motion