Brian Shields discusses pressure testing a business idea by talking to potential customers. He provides a formula to determine if an idea is worth pursuing: Market x Business Model = is it worth your time? The market is defined by the size of the problem and number of affected people. The business model considers the potential revenue and costs. Shields encourages attendees to talk to people in the hotel to see if they have the problem and would pay for a solution, to pressure test the idea before fully pursuing it.