RehearsalMark placement at begin of line: workaround?

[Xavier Scheuer]

I'm running into issue #1150 (RehearsalMark placement at start of line)
again and again.
http://code.google.com/p/lilypond/issues/detail?id=1150

Neil's workaround (see comment 2 & 5) is nice but:

1. It does not shift enough.  I'd like these "begin of line" rehearsal
marks to be printed *after the key signature* (this is also somewhat
consistent with most used practice, although there is no standard as
pointed by Reinhold).

2. This also shift rehearsal marks that are printed above "begin repeat"
bars, which are correctly placed normally (i.e. no need to shift in this
case).
See example below.

Would someone have a good "advanced workaround" in this case?
Please note that I usually do not impose line breaks, so I would like a
"general solution" (so it's not that easy).

Many thanks in advance.

%%%% Snippet begins here

\layout {
  \context {
    \Score
    \override RehearsalMark #'after-line-breaking =
#(lambda (grob)
    ;; apply shift
    (shift-right-at-line-begin grob)
    ;; call default callback
    (ly:side-position-interface::move-to-extremal-staff grob))
  }
}

\score {
  \relative c' {
    \key des \major
    \repeat unfold 8 c1 \break
    % not shifted enough with the "shift-right-at-line-begin"
    \mark \default
    \repeat unfold 8 c1 \break
    \repeat volta 2 {
      % no shift needed here, although it is applied!
      \mark \default
      \repeat unfold 8 c1
    }
  }
}

%%%%

Cheers,
Xavier

-- 
Xavier Scheuer <address@hidden>