(append
(map (lambda (x) (make-grob-property-set x 'direction
(if (odd? n) -1 1)))
- '(Tie Slur Stem Dots))
+ '(Tie Slur Script TextScript Stem Dots))
(list
(make-grob-property-set 'NoteColumn 'horizontal-shift (quotient n 2))
(make-grob-property-set 'MultiMeasureRest 'staff-position