Day 07 - Least favorite plot device employed by way too many books you actually enjoyed otherwise
Not sure about this one. Something that immediately springs to mind is how Jodie Picoult always seems to have a list of 'buttons' which must be pressed to evoke specific emotions in the mind of the reader. I actually enjoy her books; I find her characters engaging and her writing quite fluent, but whenever I read one (and I haven't read all of them by any means) I feel that she has a little list and marking off things that will make me react in certain ways. Not quite writing by formula, otherwise I wouldn't bother with them, but transparent enough to make me annoyed that I am allowing myself to be maniuplated.
Otherwise - IDENTICAL TWINS. Please don't use identical twins! I just watched 'The Prestige', which is taken from a book by an author I quite enjoy, Christopher Priest. I haven't read the book but I believe the same plot device is used. It is cheap and cheating. OF course the point in that story is that it IS cheating and leads to unforeseen consequences, but it still annoyed me. When I was a child half the children's books seemed to include twins. Especially the really far-fetched ones where whole families consisted of sets of IDENTICAL TWINS.
And the murder stories where you can guarantee that if the detective (professional or amateur) fancies someone, that someone is the murderer, or at least is lying so much about something important that it can never be. By all means have your protagonist occasionally shag a murder suspect, but not so predictably!