Comment #34 on issue 2823 by [email protected]: Patch: Fixes position of mensural c clef
http://code.google.com/p/lilypond/issues/detail?id=2823
re the double f clef, please note that this is the single case I know where - this glyph is used - alto clef is drawn as f clef (the lower one) - a clef marks not a line, but a space (the upper one) the mistaken clef mentioned in comment 33 is the KyrieUpperTriple scan.
