I was told something similar in school, but my research suggested otherwise. The source I used for this part of the article was Crime and Punishment in England: An Introductory History by John Briggs. This is the key quote: "The convicted prisoner would first be drawn through the streets on a hurdle. He – it was usually a man – was then hung from the gallows. Before he expired, however, the traitor would be cut down, disembowelled while still alive and chopped into four pieces."