Breaking Punctuation Rules

Recently, in a meeting with my critique group, I criticized an author for using too many em-dashes () in a manuscript. This author then acquainted me with an interesting online disagreement.

First, author Kate Dyer-Seeley posted a well-worded defense of the Oxford Comma. I, too, am a fan of inserting a comma after the penultimate item in a list before the and.

Then, author Kristine Kathryn Rusch (who had once been Dyer-Seelys instructor) countered with a post of her own. Her objection didnt...