Can't Resolve Colliding Noteheads...

[Glendan Lawler]

Hey everybody, I'm having a problem with noteheads in different voices colliding, and I can't seem to fix it.  I tried the standard fix from the notation:  \once \override NoteColumn #'force-hshift = # , which worked fine in a test case I did, but for some reason has zero effect in the document.  Here's the local code:

    << { \voiceOne a2.~a2.~a2. } \new Voice = "altbit" 
       { \voiceTwo fis2^\markup{ \put-adjacent #0 #-1 \sgr \dynamic "f  " } fis4 
         \once \override NoteColumn #'force-hshift = #7.5 gis2 gis4 a2 s4 } >>

I've also attached the entire code as well as a picture of my output.  Is this a bug I should report, or am I doing something wrong?

Thanks,
Glendan

In Dulce Jubilo - Source.txt
Description: Text document

NoteClash.jpg
Description: JPEG image