Unfortunately, since my actual archive pages are individual archives, this plug in is a no-go:
QUOTE
If you use monthly archives, the contents of this container will only be printed when a new year starts.
If you use weekly archives, the contents of this container will only be printed when a new month starts.
If you use another sort of archive, the contents of this tag won’t be printed at all.
Also, what I wanted was to filter the archive LISTING--that is, the MT generated list of links to the individual entries themselves.
I played some with categories, but it's cumbersome because I already have categories in my posts. And adding a secondary category to 600 something posts and then going into a separate screen for every new post to add that secondary category? Ugh.