Re: 2, 11 regression: Adding a spanner-engraver twice adds dual spanners

[Rune Zedeler]

Graham Percival skrev:
> Actually, I'd consider this a new feature, not a regression -- if you 
> add an engraver multiple times, I'd expect lilypond to draw the feature 
> multiple times.

Okay.
In this case somebody should go through engraver-init.ly to ensure that 
no engravers are added twice anywhere.
E.g. the DrumVoice is in trouble because it contains some dual engravers 
(clones of the engravers already added at Voice context)

Currently at DrumStaves, all text scripts are added twice upon each other.

-Rune