Attaching slurs to stem ends

[Carter Brey]

Hello,

   Could you take pity and tell me why the bottom voice slur in this 
extract does not respond to my request to attach itself to the stem ends 
rather than to the note heads?

\context Staff
       < \context Voice = VA { \stemUp [a'8.] a16\p}
         \context Voice = VB { \stemDown \property Voice.Slur \set  
#'attachment = #'(stem . stem) [fis'16( gis' )a']} >

Thank you so much,
Carter

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|Carter Brey (address@hidden)|
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