Using mergeDifferentlyHeadedOn and override NoteColumn #'ignore-collision = ##t

[Nick Payne]

Using these two commands together causes the merged heads of half notes 
to get filled in, so that the half note looks like a quarter note. Is 
this an unintended side-effect or expected behaviour?

%===========================
\version "2.15.12"
\relative c'' {
    \mergeDifferentlyHeadedOn
<< { a16 cis e a cis e, a cis } \\
    { a,2 } >>
<< { a16 cis e a cis e, a cis } \\
    { \override NoteColumn #'ignore-collision = ##t a,2 } >>
}
%===========================

Nick

test.preview.png
Description: PNG image