The Justice Department's top antitrust cop laid out some clues about his merger philosophy — and it doesn't bode well for AT&T's proposed $85 billion takeover of Time Warner.Both companies have pushed for "behavioral remedies" — in other words, conditions to prevent specific anticompetitive behaviors by merging companies — to address antitrust concerns.Don't hold your breath: In a speech yesterday DOJ antitrust chief Makan Delrahim said such fixes are more like temporary band-aids and hard to enforce. He was critical of specific deals approved with behavioral conditions, like Comcast/NBCU, Google/ITA and LiveNation/Ticketmaster."I believe the [DOJ] should fairly review offers to settle but also be skeptical of those consisting of behavioral remedies or divestitures that only partially remedy the likely harm," he said.Instead: He made it clear he prefers "structural" solutions, which would usually involve selling off major assets. "Behavioral remedies often require companies to make daily decisions contrary to their profit-maximizing incentives, and they demand ongoing monitoring and enforcement to do that effectively," he said. "It is the wolf of regulation dressed in the sheep's clothing of a behavioral decree."Between the lines: In this case, a structural fix could involve divestitures of Turner (the owner of CNN) or DirectTV, which has been floated in press reports. Both those assets are key to AT&T's plan for a content and delivery powerhouse.