Factual error: When Hal meets Rosie's mom, she is a large woman but her hands are skinny. If someone is the size as her character, they would have large hands as well.
Suggested correction: Actually when Hal first meets Rosemary's Mom, she is shown skinny as does Rosemary through the way that Hal sees them. It's not until later in the movie after Hal's hypnosis is gone do we (and Hal) see the "real" fat mom and rosemary and their hands do look a bit larger by then.
It is obvious that Rosemary and her mother are wearing 'fat' suits as neither women are large in real life. The suggested correction in invalid as throughout the movie, the only time Rosemary's hands appear large are in spots. (eating the taffy apple when she met Jill, and rubbing Hal's cheek when he had the goop on his eyes. Yet you never see the full body with a face in those shots.) Therefore, as I stated in the factual error, when Hal meets Rosie's mom at the end (at the party), she is wearing a fat suit, but her hands and Rosie's are skinny. It's a valid movie error.
Factual error: When Jack Black wants to be with Gywneth Paltrow, he decides to join the Peace Corps and leaves soon after. Anyone who has served in the Peace Corps or ever applied for service, knows that it takes months, and in some cases even years, to complete the application process. Therefore, it is impossible to decide to join the Peace Corps one day and commence service shortly afterwards. No one, even people who work at Peace Corps Headquarters, can swear-in as a Peace Corps Volunteer until after their first 3 months (out of a total of 27 months in country) of successful completion of training.
Factual error: When Hal goes up to the hostess in the restaurant just before Mauricio calls him, her reflection in the mirror is actually the other hostess that he sees after the phone call. And their heads don't move the same way as a mirror reflection should.
