I'd probably be annoyed if myths and magic suddenly became obviously true.

I object to myth in Sherlock Holmes when it's done stupidly—yes, Young Sherlock Holmes, despite your lack of the actual supernatural, I am looking at you—but I don't have a problem with deduction and transcendence in the same story.

(On the other hand, it annoyed the hell out of me that they gave a rational scientific explanation for all of the stuff going on in Sarah Waters' Affinity -- there, I wanted the possibility of magic.)

The only Sarah Waters I've read is Fingersmith—what's with Affinity?