Slurs between two pianos

[Urs Liska]

Hi all,

I'm at a loss with the problem shown in the attachments.

I intend to engrave a piece with two pianos (actually a piano and a 
synthesizer), where there are _many_ things going on between the two pianos.
The first is having grace notes or acciaccaturas in the "other" piano.

Writing it straightforwardly gives the attached image. When moving the 
slur engraver to the Score context (which is what I was suggested to do) 
there _is_ a difference (uncomment the \layougt definitions) but the 
result isn't really better.

Of course I could start to tweak the slurs, but I don't think that is a 
good idea at all.

Is there any way to make such cross-staff slurs behave better?

Urs

document.png
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cross-staff-slurs.ly
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