I've spoken to some economic experts, but the best explanation of the benefits of debt came from Pultizer Prize-winning writer David Cay Johnston, who was working for the New York Times at the time. And one of Oliver's clips has someone explaining the issue almost as well, relating to corporations. (Johnston's example was -- someone out of work gets hired for a job two hours away, but doesn't have a car and can't take the job. But he goes into debt to buy a car, takes the job, and earns enough money to pay off his debt and earn a good wage and build from there..)
Plus, Oliver's piece is funny, on top of it all.