Spacing anomoly

[James Lowe]

Hello,

I apologise if this is already known/fixed.

This is a based on a 'blank staff' template I use to print out

\version "2.13.35"

\score {
  { 
<<
    \repeat unfold 20 { s1 \break } 
    \repeat unfold 20 { c''1 \break } 
>>
  }
  \layout {
    indent = 0\in
    \context {
      \Staff
      \remove "Time_signature_engraver"
      \remove "Clef_engraver"
      \remove "Bar_engraver"
    }
    \context {
      \Score
      \remove "Bar_number_engraver"
    }
  }
}

\paper {
  #(set-paper-size "a4")
  ragged-last-bottom = ##f
  left-margin = 0.5\in
  right-margin = 0.5\in
  bottom-margin = 0.25\in
  top-margin = 0.25\in
}

If I try to compile this specific ly file I get 

---
Processing `/Users/james/Desktop/Lilypond Work/Misc/blank_staves.ly'
Parsing...
Interpreting music... [8][16]
Preprocessing graphical objects...
Finding the ideal number of pages...
Fitting music on 1 or 2 pages...
Drawing systems...
warning: couldn't fit music on page: overflow is 6.317630
warning: couldn't fit music on page: overflow is 9.970964
Layout output to `blank_staves.ps'...
Converting to `./blank_staves.pdf'...
success: Compilation successfully completed
---

but the last pair of staves flows off the bottom.

If I remove all the \layout { } then it all fits. This seems odd because the 
layout is actually removing 'stuff' in the first place. So this is counter 
intuitive to me.

Sorry if this is wasting anyone's time.

James