Here's a semi-literary thought:
I started reading Shirley tonight, and it's the second Penguin Classics edition of a Charlotte Bronte book I've bought; the first was Villette for a Lit class last semester. I was startled by the number of notes added to Villette, sometimes up to 40 notes in an 8-page chapter, but I assumed it was just this editor in particular, Helen Cooper - who also wrote the introduction to that edition. The endnotes were so numerous, in fact, that when I couldn't finish the book in time for our last class discussion of it, I read the endnotes of the chapters I hadn't gotten to, and felt I had enough information to join class discussion. Brontephiles will probably want to shoot me for this.
At any rate, the first two pages alone of Shirley have proven to me that it wasn't Helen Cooper in particular who seems to think that Bronte's work can't stand up to a modern audience without a minute dissection of period detail and context. I'm on the second page of the novel, and the seventh endnote. The first two notes were actually on: 1) the heading, "CHAPTER ONE," and 2) the title of the chapter, "LEVITICAL."
As in Villette, when the chapter heading is annotated it's for a general note on the entire segment to follow, such as historical editorial response to that portion of text. When the chapter title is annotated, it usually involves an explanation of the roots of the word or phrase used as the chapter title, and its bearing on the themes of the book. These all - to my mind - consist of commentary that belongs in the introduction or a biographical sketch and not in interjections to the text itself.
I admit I've become an endnote-hound since I came to university; it helps a lot to understand the subtle little details, and it's fun to learn about them, too. However, endnotes should be reserved for information that leads to an immediate illumination of an archaic word, phrase, or custom, or the translation of passages in a different language. I don't understand why certain modern editors think it's necessary to continually interrupt the text with contextual or biographical information that only really adds meaning after the first complete reading, when the reader is familiar with the novel as a whole. It's almost as if editors think these novels would be otherwise meaningless to the uninformed modern reader, which is an insult to the work and the reader. One of the reasons these are great works of literature is that they can stand up, centuries after their first conception, and make an impact on anyone who understands what it's like having human feelings.
I don't know if this is a regular trait in Penguin Classics editions, or a general feature of trendy modern editions - and I do know that it's not an earth-shattering issue, either - no one's putting a gun to my head and forcing me to read every annotation. It just disturbs me a little; talk about not being able to see the forest for the trees. If proving a novel is autobiographical or politically motivated becomes more important that appreciating its artistic worth undisturbed, what does that mean for literary criticism in general? Or does it mean anything at all? I'm probably overreacting.