My theme apparently wraps every  in another set of <a href=""></a> tags that point to the source for the image. If you’re trying to generate galleries with a shortcode using fancyboxes, this default behavior is going to bite you in the ass. I forced the behavior to what I want/expect by copying assets/js/even.js and assets/js/main.js from themes/even into my blog root assets/js/. Then I hacked out the fancyboxes references in both files and regenerated. Boom, galleries work, and I didn’t lose anything of value in any previous posts. It’s a win/win for my specific situation.