I think this is partially because Gwyneth's story was the original explanation for the Bell that McKillip discarded because it didn't work for the novel. She liked it, though, and wanted it to appear in the story somehow. (From this interview (http://www.greenmanreview.com/book/interview_mckillip_2008.html).)

Speaking of McKillip, did you see the special edition of Green Man Review (http://www.greenmanreview.com/whats_new.html) dedicated to her? It was published this past Sunday.