Three voices plus tie in RH - notation best practice?

[James Harkins]

Hi, a "notational correctness" question rather than a lilypond technical 
question, hope that's okay.

A student brought in some work today, some of which calls for three voices in 
the right hand of a PianoStaff. Minus expressive marks, the lilypond example 
below gets the point across, but I wonder if there's a better way? The 
collision at the beginning of bar 2, between the a4~ a2 tie and the c# in voice 
1, seems inevitable but it isn't pretty. (\tieDown looks even worse.)

So, those of you with a notation reference or two in your library, how would 
you handle this?

Thanks!
James

PS Sorry for the non-tiny example. In this case, the voicing is complex enough 
that I wanted to be explicit about all the new voices.


\version "2.14.2"
\include "english.ly"

\score {
  \new PianoStaff <<
    \new Staff {
      \key d \major
      \numericTimeSignature
      <<
        \new Voice \relative c'' {
          \voiceOne
          r2 r8 cs?4.~ cs2
        }
        \new Voice \relative c'' {
          \voiceTwo
          a16 fs e fs \repeat tremolo 2 { e fs } \repeat tremolo 2 { e fs } a16 
fs e fs
          \repeat tremolo 4 { e fs }
        }
        \new Voice \relative c'' {
          \voiceThree
          a2. a4~ a2
        }
      >>
      r2
    }
    \new Staff {
      \key d \major \clef bass
      \numericTimeSignature
      <<
        \new Voice \relative c' {
          \voiceOne
          g16 b c b \repeat tremolo 2 { c b } \repeat tremolo 2 { c b } g16 b c 
b
          \repeat tremolo 4 { c b }
        }
        \new Voice \relative c' {
          \voiceTwo
          g2.\sustainOn g4~\sustainOn g2
        }
      >>
      r2\sustainOff
    }
  >>
}


--
James Harkins /// dewdrop world
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