> Here's something you can do in 2.19.83:
>
> %%%%
> \version "2.19.83"
>
> \tagGroup #'(screenOut midiOut)
> nc = {\tag #'midiOut <c c'> \tag #'screenOut c' }
> nd = {\tag #'midiOut <d d'> \tag #'screenOut d' }
> myScore = {\nc \nd \nc << \nd s~ >> \nd}
> \score {\keepWithTag #'screenOut \myScore \layout{}}
> \score {\keepWithTag #'midiOut \myScore \layout{}}
> %%%%
And empty chord works in place of the spacer too:
%%%%
myScore = {\nc \nd \nc << \nd <>~ >> \nd}
%%%%
it works, and it works also on 2.21.00
But it doesn't work in a bit more complex situation. I make some test and I will be back.
Thanks a lot, g.