Re: Issue 442 in lilypond: Enhancement: RemoveEmptyStaffContext shouldn't reduce PianoStaff to one staff

[lilypond]

Comment #8 on issue 442 by n.puttock: Enhancement: RemoveEmptyStaffContext  
shouldn't reduce PianoStaff to one staff
http://code.google.com/p/lilypond/issues/detail?id=442

I'm afraid I agree with David here, even though the patch looks pretty good.

This behaviour should be the default for a PianoStaff, so either a  
\consist-ed engraver or property set in the PianoStaff context would be  
preferable.

David, I'm pretty sure we already have support for spacing within a  
grouping context via StaffGrouper: it's used in PianoStaff (via the  
addition of Vertical_align_engraver and setting topLevelAlignment = ##f).