While I understand your point, BK, as someone with an English degree, I must at least offer the opinion that writing grammatically is not necessarily "arch", it's simply being correct. The easiest way to differentiate between who and whom is that "who" always takes a verb.
English degrees are for people with English degrees - books are written by people and those people have been bending "rules" since the year One and those rules have changed constantly over the years. What was once looked on as a horrible mistake is now accepted. And I agree with John G. about the voice of the book. Anyone can write a grammatically perfect book, but that does not make the book well written or even interesting. I've been bending rules about everything my whole life. Some I've bent are now common practice. Some aren't. I've been bending grammar rules since book one. I had three proofers on that one, too, and the comma thing drove me batty and I just refused to do it in certain instances because, for me, the rhythm of the narrator in that book was very specific and I would not allow overdone punctuation to make reading a line that should sail to become herky-jerky thanks to six commas. Will not do it. I do the stuff that's important and that makes sense and that doesn't hurt the flow. And I'm not the only one.
Spelling and laziness are something wholly other and I don't like either. But some awfully great books have first edition errors that got by proofers - fixed in subsequent editions. Most recently, J.K. Rowling's books, each and every one, have had blatant errors in them that have been corrected in subsequent printings, making those error copies even more valuable. East of Eden has an error. Agee's A Death in the Family has an error. And on it goes. You try to catch it all, but sometimes one or two get by the best of proofers.
