Re: conditional formatting

[James Bailey]

I can't really use Scheme (other than find and replace), so maybe this doesn't 
solve what you need, but what about creating separate variables with the staves 
that you want and simply commenting an appropriate \score ? i.e.,
\version "2.12.3"

piccolo = \relative a' { a c' a e' e c a e }

instrument = { a, c' a e' e c' a e'}

instrumentTab = {
  a,4\5 c'\2 a\3 e'\1
  e\4 c'\2 a\3 e'\1
}

withTabs = \new StaffGroup <<
   \new Staff \instrument
   \new TabStaff \with { instrumentName = lute } \instrumentTab
>>

withoutTabs = \new StaffGroup <<
   \new Staff \with { instrumentName = piccolo } \piccolo
   \new Staff \with { instrumentName = lute } \instrument
>>

%\score { \withTabs }
\score { \withoutTabs }