If history were a movie, what would be the most egregious plot holes?

Hate that smarmy, too-good-to-be-real Christmas episode of World War I? Annoyed by the lazy montage scene that took us from the first airplane to the Moon in just 66 years? Think "rocks fall, all the dinosaurs die" was just a total cop-out? Here's a fun Reddit thread you will appreciate, pointed out to me by Karen James.