Actual progress on this Ph.D revision has been quite slow. My current efforts are on improving the focus of the thesis. One of the criticisms the examiners made (somewhat obliquely) was that it wasn't very clear exactly what my subject was: musicology? music information retrieval? computational musicology? And the reason for this was that I failed to make that clear to myself. It was only at the writing up stage, when I was trying to put together a coherent argument, that I decided to try and make it a story about music information retrieval (MIR). I tried to argue that MIR's existing evaluation work (which was largely modelled on information retrieval evaluation from the text world) only took into account the music information needs of recreational users of MIR systems, and that there was very little in the way of studying the music information seeking behaviour of "serious" users. However, the examiners didn't even accept that information retrieval was an important problem for musicology, nevermind that there was work to be done in examining music information needs of music scholarship.
So I'm using this as an excuse to shift the focus away from MIR a little and towards something more like computational musicology and music informatics. I'm putting together a case study of a computational musicology toolkit called music21. Doing this allows me to focus in more detail on a smaller and more distinct community of users (rather than attempting to studying musicologists in general which was another problematic feature of the thesis), it makes it much clearer what kind of music research can be addressed using the technology (all of MIR is either far too diverse or far too generic, depending on how you want to spin it), and also allows me to work with the actually Purcell Plus project materials using the toolkit.