Sorry to jump in here as someone who just (re-)signed up for the list, but I actually find
+Note that @code{[} and @code{]} do not enclose the notes to be
+slurred.
potentially confusing. I would say something like either "Note that the first note of the slur appears before the opening @code{(}" or "Note that the @code{(} marking the beginning of a slur appears after the first note of the slur", and ditto for beams. (I might say "note pitch" instead of note too, but that's a more minor point.)
+Ties and slurs are indicated by adding special codes after the
+notes to which they apply.
Could maybe be worded as "Slurs are indicated by adding special codes after the first and last note of the slur", under the theory that you don't add that markup to all notes in the slur (assuming there are at least three). Though then you have to drop ties from that sentence. This one I think is less important as well.
Evan