Comment #12 on issue 2858 by [email protected]: Document \shape music
function
http://code.google.com/p/lilypond/issues/detail?id=2858
The value of implementing \shape as both an override and tweak is so
the tweak form is available for modifying the ties between individual
notes in chords. (Incidentally, the need for this in current versions
of LilyPond was embarrassingly shown by Bertalan Fodor recently, see
http://bartruffle.blogspot.co.uk/2012/09/musescore-vs-score-vs-lilypond-vs.html#more
)
But, like Keith, I think the override form is clearer
for normal single-item use.
Trevor