Davydov wrote:[...] There are now only 8 proposed broad categories, with optional 'sub-genres' that depend on the style of a work instead of its instrumentation. This will enable searches for operettas, symphonies, motets, etc. for the first time. [...]
I was not aware that there was one style for operettas, one style for symphonies, one style for motets, etc.
These are
types of pieces, each group of which could encompass one or more styles among its representatives -- especially when viewed from one era to the next, or even from one composer to another in some cases.
"Concerto" is a specific type of work; it seems too limiting to include also
other concerted works (which is why I am partial to "concerted works" as the category name).
I propose
again that we dispense with the term "genre" (as well as "sub-genre"). If we're not going to have concurrent indexing systems acknowledging the performance forces/venues separately from the types of works, then the 8 main headings could simply be called "Main Categories," with the "sub-genres" likewise called "Sub-Categories."
"A libretto, a libretto, my kingdom for a libretto!" -- Cesar Cui (letter to Stasov, Feb. 20, 1877)