mus=\relative c' {
      \voiceOne
      \time 3/8
      <c g'>8(-- <d g>-- <es g>--) |
      <es a>--( <es b'>-- <es g c>--) |
}

{<>^"Bad case" \mus}

{
  <>^"These cases are fine"
  \transpose c d \mus
  \transpose c b, \mus
}

{
  <>^"Also fine"
  \autoBeamOff
  \mus
}

{
  <>^"Bad"
  \override Beam.positions = #'(2 . 2)
  \mus
}

{
  <>^"Fine"
  \override Beam.positions = #'(1.9 . 1.9)
  \mus
}

{
  <>^"Fine"
  \override Beam.positions = #'(2.2 . 2.2)
  \mus
}

{
  <>^"Fine"
  \override Beam.positions = #'(2 . 2.1)
  \mus
}

{
  <>^"Bad"
  \override Beam.positions = #'(1.0 . 1.0)
  \mus
}

{
  <>^"Fine"
  \override Beam.positions = #'(1 . 1.1)
  \mus
}

{
  <>^"0"
  \override Beam.positions = #'(0 . 0)
  \mus
  <>^"0.4"
  \override Beam.positions = #'(0.4 . 0.4)
  \mus
  <>^"0.8"
  \override Beam.positions = #'(0.8 . 0.8)
  \mus
  <>^"0.9"
  \override Beam.positions = #'(0.9 . 0.9)
  \mus
  <>^"1"
  \override Beam.positions = #'(1 . 1)
  \mus
  <>^"1.2"
  \override Beam.positions = #'(1.2 . 1.2)
  \mus
  <>^"1.4"
  \override Beam.positions = #'(1.4 . 1.4)
  \mus
  <>^"1.6"
  \override Beam.positions = #'(1.6 . 1.6)
  \mus
  <>^"1.8"
  \override Beam.positions = #'(1.8 . 1.8)
  \mus
  <>^"2"
  \override Beam.positions = #'(2 . 2)
  \mus
  <>^"2.2"
  \override Beam.positions = #'(2.2 . 2.2)
  \mus
}