The CFO of AT&T John Stephens dropped a few more clues into his address of the Deutsche Bank Conference this week on how AT&T sees the benefits of its proposed merger with Time Warner, presuming that ever happens. The key, as we have said in the past, is that AT&T believes that it has better data about its customers, than Time Warner could possibly have about its viewers, and that buried in this data is a revolution in advertising. We’re not so sure. When you think about operators who rely on big data and analytics, you think of Netflix and Amazon first and foremost, and Netflix knows who its customers are by maintaining a direct relationship with them, and by…