MIDI inputs not selected here or on the Sync page (see “Advanced MIDI - The External Control Bus inputs”) are available to other programs.For example, if you lock a control surface to the Main Mixer, you will always have control over levels, pans and additional channel strip parameters - see “Remote controlling the Main Mixer” and “Remote controlling multiple mixer channels”. You could also have dedicated controls for transport, Undo/Redo, sequencer track MIDI focus selection, etc.