for example, go to http://musicbrainz.org/release/ceba7d99-1a3f-45b3-8516-114deaad998a
1. click "edit relationships"
2. check all remix tracks (ie, tracks 1-8)
3. select "Batch-add a relationship to recordings"
4. attempt to relate all remix tracks to the original mix (track 9): http://musicbrainz.org/recording/c5ee869c-3f4f-4a07-b08b-e8a0197db9be
5. you will get the error message: "This relationship type is deprecated" (likely referring to the default option "earliest release"), but...
6. even when you switch to the "remixes" option, the error message will not dismiss itself, preventing you from proceeding with the edit. (both "change direction" and "done" buttons are grayed out.)

in fact, the error message prevents you from proceeding with any batch recording-to-recording relationship edit.

setting up this relationship is still possible within each recording page itself.