I’ve written a piece for io9. It’s “An Open Letter to the Writers and Directors of Hot Tub Time Machine”, and includes such over-the-top lines as:
When Clark Duke interrupts his parents mid-coitus, he temporarily disappears from existence. Mathematical models demonstrate that this is not what would happen. It has been shown conclusively that he would fade from existence a bit at a time, starting with images in photographs.
Sufficed to say, the entire article is meant as a joke. Please make sure you read the comments section. About 1/3 of them are along the lines of “Dude. It’s a movie!”, and the rest are responses along the lines of, “Uh… it was a joke.”