automatic invisible unmetred linebreaks

[Monk Panteleimon]

Hello.
I am setting unmetred chant, using \set Score.timing = ##f.
Previously I have always inserted
\bar"" \break 
wherever I wanted a linebreak without a barline. 
Now I have discovered that I can use barAlways and defaultBarType = "" to 
insert invisible barlines between all the notes, which makes the linebreaks 
happen more or less automatically. Using this method would make my work a lot 
quicker, but the slurs look funny because they are avoiding the invisible 
barlines. 
Can I make the slurs ignore the invisible barlines?

Also, I thought that \bar"" took up no space at all, but now I'm not sure. Are 
the invisible barlines taking up space; and if so is it possible to change 
the padding on all invisible barlines without also changing the padding on 
visible ones?

I'm running Lilypond 2.10 on Linux

Here's an example file :
\version "2.10"
\score {
\relative c'' {  \set Score.timing = ##f \set Score.barAlways = ##t \set 
Timing.defaultBarType = "" \key g 
                \major \autoBeamOff 
b4 c8([ d]) b4.( g8) a([ c]) b([ a]) g4( a) b4  c8([ d]) e4 d8([ c]) d4 c b4.( 
a8) g([ a]) b4  a b8([ c]) d2 
d4 c b8([ c]) d4 e d c8([ b]) d4( c) b g8([ a]) b4 c8([ d]) b4 b8([ g]) a([ c 
b a])  g4 a b2  
        }
\layout { ragged-last = ##t \context { \Staff 
\remove "Time_signature_engraver" \remove "Bar_number_engraver"  } 
        } 

} 

Many thanks.

Fr. P