Second John occupies a rather peripheral place in the New Testament canon. Consisting of a mere thirteen verses and often viewed as a kind of abstract of 1 John, the letter has traditionally not garnered much individual attention. While scholars have long noted that the opening address of the letter is ambiguous, in some cases even problematic, the received reading that is printed in all Greek editions of the New Testament for the last 150 years is ἐκλεκτῇ κυρίᾳ and is typically translated as "to an elect lady." The nearly universal view in modern scholarship is to take "elect lady" as a metonym for a church that is metaphorically personified as a woman. Drawing upon a wide range of evidence that includes Greek papyri, New Testament manuscripts, and a host of other sources, this study shows that the received address printed in all editions of the Greek New Testament is not correct. Rather, the address should be rendered Ἐκλέκτῃ τῇ κυρίᾳ and translated "to the lady Eclecte" so that the principal recipient of the letter is a named woman. This reading makes far more sense with the letter as a whole and makes it the only text in the entire New Testament canon addressed to a woman.
This is a textual analysis of John's second epistle. Blumell goes to extensive lengths to make his argument. This is not my type of analysis, so I can't address that aspect. I would say he makes his case, but since this is not a university press publication, I don't think the effect will go very far. I hope he made similar arguments in relative academic journals. Having said that it is an academic work, though but generally written in a fashion that is easy enough to understand. He doesn't define his terms and makes some assumptions about who will read his book. There is a lot of Greek, that may scare some people off, though full transitions and references are available. Still it is an academic read.