Porn mogul Larry Flynt took the stand Tuesday for the first day of his federal trademark infringement trial against nephews Jimmy Jr. and Dustin, who have launched their own “Flynt” adult film company. “Inferior products” and “knock-off goods” were among the phrases the elder Flynt used to describe their films. “Your clients are focusing on the boob element, so to speak,” he said in court. “I just think that’s sort of passé, and guys are moving past that. That’s only my opinion.”