Ah, that works, but it has another problem: there's no way to configure a sticky block to appear on only some pages and not others.
We have both course sites and a number of student/faculty/trustee groups in the site, and the latter set won't want the library block. (Some turn off all blocks entirely) We'd like one we can turn on by default for course sites but not the others, and I'm not sure sticky blocks can do this. (It looks like you have to change site config files to set default blocks)