Stanzas with different rhythms

[Fr. Samuel Springuel]

I’m trying to apply the techniques for switching to an alternative melody for a 
stanza from here: 
http://lilypond.org/doc/v2.20/Documentation/notation/stanzas#stanzas-with-different-rhythms

So far the switch to the alternative melody is working alright, but the switch 
back is giving me trouble.  If I put the \unset command as indicated (one 
syllable before it is supposed to apply) then the words switch back to the main 
melody on the wrong note (one note too soon).  If I put the unset command 1 
syllable later, then the words disappear (presumably because they're sticking 
with the alternative melody which has run out of notes).  Have I misunderstood 
something about how this technique is supposed to work?

\version "2.20.0"
\language "english"

global = { \key f-sharp \minor \time 4/4 }

music = {
  f-sharp'4 e'8 f-sharp' << { \voiceOne a'4. a'8 } \new Voice = "v3" { 
\voiceTwo \teeny a'4_\markup{v.3} a' } >> \oneVoice |
  g-sharp'8( f-sharp') g-sharp' e' f-sharp'2 \bar "|."
}

verseII = \lyricmode {
    Tak -- ing our way, you walked with us there.
}

verseIII = \lyricmode {
    Gen -- tle \set associatedVoice = "v3" and strong
    \set associatedVoice = "mel" %  words come back on wrong note: 1/8 too early
    one,
    %\set associatedVoice = "mel" % makes all subsequent words disappear
    Lord of our way.
}

\new Staff
<<
    \new Voice = "mel" { << \global \music >> }
    \new Lyrics \lyricsto "mel" { \verseII }
    \new Lyrics \lyricsto "mel" { \verseIII }
>>


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Fr. Samuel, OSB
(R. Padraic Springuel)
St. Anselm’s Abbey
4501 South Dakota Ave, NE
Washington, DC, 20017
202-269-2300
(c) 202-853-7036

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