I watch Masterchef and one of the presenters/judges cannot get this right. Drives me batty. I spent an hour one day in my previous job explaining the rule to my manager and he did not understand it. Even when I told him to take the other person out of the sentence. My previous job was copy-editing; you'd think the manager would understand basic grammar.
People who fail to use semi-colons with "however" (when required). Semi-colons are the best.
Outside of a dog, a book is man's best friend. Inside of a dog it's too dark to read. - Groucho Marx