fixing MetronomeMark

[Kieren MacMillan]

Hi devs!

The two MetronomeMark behaviours I would like to fix (or $pon$or for  
fixing) are:

1. The break-alignment situation (q.v., <http://code.google.com/p/ 
lilypond/issues/detail?id=684&can=1&q=metronomemark>).

Any recent movement/news on this issue?
Can this be fixed in Scheme or only C++?


2. The fact that MetronomeMarks collide painfully when extracted  
parts have multi-measure rests, e.g.

\version "2.12.2"
\layout { \context { \Score skipBars = ##t } }
mmProblem = \relative
{
  \tempo \markup { "My first tempo marking" } R1*5
  \tempo \markup { "My second tempo marking" } R1*3
  \tempo \markup { "My third tempo marking" } R1*3
}
\score { \mmProblem }

Can anyone see a way to indicate that "this MetronomeMark has a  
minimum measure length of X", so the collisions seen in my example  
would not happen?


Thanks,
Kieren.