Reducing fingering font size

[Nick Payne]

I have been trying to slightly reduce the font size for guitar fingering, as
the default size of number touch when adjacent notes in a chord have
fingering, as in the attached file.

However, I can't get the numbers any smaller than the default. If I use

\override Fingering #'font-size = #0

Then the numbers are twice as large as the default, and 

\override Fingering #'font-size = #-6

gives exactly the same size as no size override, whereas my reading of the
documentation (sect 1.7.1 in lilypond.pdf) is that using #0 should give the
default size and #-6 should give half that size.

Ly file is attached. I'm using 2.11.63 on Vista. When I uncomment the
\override commands in the three voices, the size of the numbers doubles.

Nick Payne

Pezzo-Tedesco.ly
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