I am re-engraving music based on the attached image. Notice that the original editor tightened the horizontal spacing between the notes on the syllables "De-" and "Pa-." This was done to mimic the Gregorian chant neumes on which the music is based.
Could someone recommend how to achieve this in Lilypond? The best I have come up with is:
normalSpacing = { \override NoteColumn.X-extent = #'(1 . 6) }
tightSpacing = { \revert NoteColumn.X-extent }
This approach has a number of downsides (can't start or stop in the middle of a slur; can't squeeze multiple notes underneath a lyric syllable).