Re: collision-detecting engraver?

[Kieren MacMillan]

p.s. Perhaps a more helpful working example would be:

\version "2.19"

theNotes = {
  \repeat unfold 3 { R1 }
}

theChords = \chordmode {
  g1 \tag #'moved { \once \override ChordName.X-offset = #2.5 } g1:7 c1
}

theDynamics = {
  s1 s\mf s
}

\score {
  \removeWithTag #'moved \new PianoStaff <<
    \new Staff \theNotes
    \new Dynamics \theDynamics
    \new ChordNames \theChords
    \new Staff \theNotes
  >>
}

\score {
  \keepWithTag #'moved \new PianoStaff <<
    \new Staff \theNotes
    \new Dynamics \theDynamics
    \new ChordNames \theChords
    \new Staff \theNotes
  >>
}