\lyricsto not working with Devnull

[Ted Walther]

I'm using the Devnull trick mentioned by Mats Bengtsson, referenced in
this post:

     http://lists.gnu.org/archive/html/bug-lilypond/2006-06/msg00177.html

I am using lilypond version 2.9.17.

The lyrics should follow the soprano melody.  And they do, but I notice
that lyricsto isn't centering the words below the notes.

Am I doing something wrong, or is this a bug?

Here is the resulting PDF:

   http://reactor-core.org/~djw/Doxology.pdf

And here is the score section:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\score { <<
     \new Staff <<
       \global 
       \clef treble 
       \partcombine \soprano \alto
     >>
     \new Devnull = "rhythm" \soprano
     \new Lyrics \lyricsto "rhythm" \Words
     \new Staff <<
       \global
       \clef bass
       \partcombine \tenor \bass
     >>
   >>
   \layout {
     \context { \GrandStaff \accepts "Lyrics" }
   }
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

--
           It's not true unless it makes you laugh,                           
      but you don't understand it until it makes you weep.

Eukleia: Ted Walther
Address: 2459 E 41 Ave, Vancouver, BC  V5R2W2 (Canada)
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