Alignment of notes across staves with negative horizontal shift

[Li Jie Wong]

Hi,

Suppose I have the following system:
<< \new Staff << a' \\ e' >> \new Staff << a' \\ e' >> >>

I can nudge one of the notes to the right, keeping the alignment of
the other three notes using an override of NoteColumn's force-hshift
property.

How do I nudge one of the notes to the left while keeping the
alignment of the other three notes?

If I try to use a negative force-hshift, the alignment of the notes in
the staff are okay, but the notes in the other staves are aligned to
the nudged note.

Thanks,
Li Jie