Now you have got me in trouble with my wife, who is always going to be wondering where her iPad has gone.
Yes, and works especially well with Hauptwerk. The picture below shows HW on the Mac screen, and two identical layouts - with all controls sync'd. HW is explicitly designed to keep multiple input and output panels correctly sync'd. Using the echoing functions of HW, no matter where I make a change, all three displays stay sync'd up. Even if you are doing separate left and right jambs, there are likely some couplers, etc., that need to be sync'd between.
I do need to change one line in my St Annes instructions - for this to work, always suppress output (echo) must be deselected. We do want HW to echo any received command to ensure all displays are sync'd.
And like my other post - I recommend that MD just do the display and controls - let HW handle the heavy lifting of combinations. It has mind numbing set of combination controls. I stopped with controls for 35 in my layout for exactly that reason.
And you have got me energized to update my St Annes layout with more functionality.