How did you find THAT?

The Midwest turns up where you least expect it, like smack in the middle of the article, "Identifying Benjamin W. Cohen of New York and New Orleans," by Teri D. Tillman, CG, in the current National Genealogical Society Quarterly (member$hip required, earlier blogged here).This article is a wonderful genealogical tour de force. Her key piece of evidence that New York City doctor Benjamin W. Cohen and New Orleans dentist B. W. Cohen were the same person comes from -- a 10 Feb 1842 letter now in the archives of the University of Notre Dame! (page 252)

I love unconventional sources as much as the next guy, but what's the story behind the story? How did the author ever get the idea that it might be worth trolling the archives of a Midwestern Catholic university for information on a Jewish dentist in Louisiana?