If you have deleted a bibliographic record which appears on someone's list, the title will remain on the list but the original biblionumber will not be output to the template. Since virtualshelfcontents stores entries by shelfnumber + biblionumber, you can't delete something without a biblionumber. This makes it impossible to remove something from a list after the bibliographic record has been deleted. This makes it impossible to mitigate the effects of Bug 7252 by removing the deleted item from a list.
Wonder if this still is true..
I think it is resolved : When I delete a record which is on a list, the title is not shown anymore in the list. M. Saby
Seems to be fixed, please reopen if I am wrong.