Questions about PianoStaff Braces

[Jonathan Wilkes]

Hello,
     I'm having trouble tweaking the Brace at the beginning of a system. 
My test code is below; basically, I'd like to make the brace oonnecting 
three staves less thick.

That brings me to my second question: 

\score {
        \new PianoStaff 
%         \override PianoStaff.SystemStartBrace #'thickness = #0.2
          <<
          \new Staff = "rh" {
          <<  { c' d' e' f' }
            \new Staff \with { alignAboveContext = "rh" } { c' d' e' f' }
          >>
          \break
          c' d' e' f'
          }
          \new Staff {
          c' d' e' f'
          c' d' e' f'
          }
        >>
}

\paper {
        indent = 0
}

%\layout {
%       \context { \PianoStaff
%               \override SystemStartBrace #'thickness = #0.2
%       }
%}

http://imslp.info/files/imglnks/usimg/d/dd/IMSLP00510-Debussy_-_Preludes__Book_2.pdf

Durand

durand.PNG
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lilypond.PNG
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