I used musicbrainz picard to look up copy of this CD: http://musicbrainz.org/release-group/9dd64989-0ca3-3016-806d-8b2f31691c35, which had a discid not currently in the database. Picard offered to look up the disc manually, which I clicked. This opened up my browser, which said it had found a CD stub, and would I like to import it? It also put up two searches for the discid (artist & album title). There is no indication that either of these searches will produce any results. If I chose the naive route and imported the CD stub, I would have to notice when the editing process goes to fill in tracks that there was already an instance of this album in the database. Since I have been burned by this awkward process before, I knew that for a commercial record like this I should ignore the stub and search for a release that just needs a new discid. The page with the CD stub & search buttons should indicate in some way that it seems likely that a search will result in possible matches rather than just offering the two searches.