Harm, With respect, I'm far from convinced that this is a good idea, but I will continue to think about it. Thoughts so far:
* The user provides music for the appearance of the mark at the beginning or end of a line, but can he control what happens in the middle? They seem to stack vertically. What if the user would prefer them to be side by side? * The regression tests cover only line breaks. The unbroken appearance is not covered. * I am concerned about the complexity of this function as it deals with mark sequence numbers. I'm skeptical that it's a fair trade for what it offers. * I struggle with the semantics of using one event and grob to do double duty, e.g. as both a fermata and a rehearsal mark. One of my stale experiments is a performer that inserts rehearsal marks into MIDI files. I don't relish the thought of trying to extract a MIDI-compatible rehearsal letter/number from such a mishmash. https://codereview.appspot.com/577180043/
