" They don’t have to be sentences, they could be divided by commas, they could be divided by semi-colons; there’s a class of people who get very worked up about such things - they’re lonely people - they tend to have stains down the front of their shirts - they’ll tell you that dashes should be used only to subordinate complete sentences. You must forgive them. "

― Mark Forsyth , The Elements of Eloquence: How to Turn the Perfect English Phrase