Positioning of two voices is inconsistent

[James]

Hello,

\version "2.14.1"

 

 { << { e'1 } \\ { e'''1 } >> |  }

 { << { e'''1 } \\ { e'1 } >> |  }

 { << { e'1 } \\ { e''1 } >> |  }

 { << { e''1 } \\ { e'1 } >> |  }

 { << { e'1 } \\ { e1 } >> |  }

 { << { e1 } \\ { e'1 } >> |  }

I don't understand why the notes are not aligned in all cases.

Is this expected engraving/LP behaviour?

Attached png showing output.

--
--

James

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