-shiftOn = \override NoteColumn #'horizontal-shift = #1
-shiftOnn = \override NoteColumn #'horizontal-shift = #2
-shiftOnnn = \override NoteColumn #'horizontal-shift = #3
+mergeDifferentlyDottedOn = {
+ \override Staff.NoteCollision #'merge-differently-dotted = ##t
+}
+mergeDifferentlyDottedOff = {
+ \revert Staff.NoteCollision #'merge-differently-dotted
+}
+
+mergeDifferentlyHeadedOn = {
+ \override Staff.NoteCollision #'merge-differently-headed = ##t
+}
+mergeDifferentlyHeadedOff = {
+ \revert Staff.NoteCollision #'merge-differently-headed
+}
+
+shiftOn = \override NoteColumn #'horizontal-shift = #1
+shiftOnn = \override NoteColumn #'horizontal-shift = #2
+shiftOnnn = \override NoteColumn #'horizontal-shift = #3