Seriously, I think many things like that can be chalked up to a phenomenon someone needs to make a really good term for, where the gradual, ongoing rewriting of history changes the way later events in 1897 "originally" happened. For instance, [spoiler]Beth the ghost's story to Julia which cannot possibly be the original story.[/spoiler]
Closest thing I can think of is the subgenre of Science Fiction known as Alternate History. An event happens that causes time travel for one or a group of people, and their actions gradually change the timeline. Googling Connie Willis, Dr. Harry Turtledove and Eric Flint will get you a TON of information on how various authors have written in this framework.
Then of course there's Classic Trek's "City on the Edge of Forever" where a random action by a character who accidentally time travels destroys an entire future because someone who was supposed to have died doesn't.
Like the various explanations of the ripped shirt -- esp. Midnite's.
Course the real explanation is soaps and their gratuituously shirtless hunks. I remember my best friend was hooked on a soap back in the early 80s -- and how we joked about there being a clause in the actors' contracts requiring one shirtless scene a week for no externally logical reason (we checked the frequency, kenneth.) Put me in the schitzoid Gemini camp of trying to make plot sense of it, while having no objection whatsoever to enjoying the scenery.
I knew the wording on the curse sounded familiar. <bops self on head> As if we didn't hear that tape recording enough times for me to remember it was ripped off their explanation about Adam.
Thanks about my questioning Magda's logic on killing Quentin, and LOL on the Curses for Dummies. Maybe we need a second copy for Angie and her "whoever loves you willl die".
Jeannie