4. He Could Convince Walt To Turn Himself in/Become An Informant
Walt has been 'out' for three months or so by the end of 'Gliding Over All', suggesting that his life is right where he wants it to be. His family is on side, he's got more money for them than he could ever imagine, and he's seemingly got away with it. Hank breaking this news to him could tear Walt apart - and we know how Hank deals with awkward situations. Once he comes back with the coffee, Walt could just tell him everything, frame Jesse, Todd and whoever else is left (not many, really). This would tie in with Walt 'the actor'. He might be giving himself up, but he's not going down alone.