I've finished the process of converting uses of <argument> for marginal labels to the <label> tag. I had to regenerate the schema again, because in the documents affected (the Sonnets, Forest, Le Bon Mariage and Ville-Thierry), there are now occurrences of <label> where it did not appear before, so I regenerated the odd file:

java -jar /home/mholmes/saxon/saxon9he.jar -it:main -o:/home/mholmes/WorkData/French/Claire_data/mariage_5/mariage_2012-01-30.odd /home/mholmes/WorkData/tei/sf_repo/trunk/Stylesheets/tools/oddbyexample.xsl corpus=`pwd`/

then edited the file manually to add @type to <label> (I'm doing this in the TEI namespace, although strictly speaking I probably shouldn't, but I don't see why <label> doesn't have @type in the first place).

I've written to EGB and GM to explain the change, and I'm now going to look at the documentation to see what needs changing there.