I can't imagine Hank confronting Walt and giving him a chance to lie without trying to build a case first. What if Walt ran? Then Hank would have nothing. Then there's the question of how will it look to Hank's subordinates and co-workers that Heisenberg was under Hank's nose all this time? That's why Hank's boss got canned over Gus Fring. It's all complicated. I think Hank goes after local dealers to try and get corroborating evidence and starts with one Jesse Pinkman. The potential for conflict is delicious, and we have Lydia and the Czech Madrigal element who are going to want their supply to continue. Hell.....could Walt play them
off as the masterminds and himself more of a victim? Maybe he's turning state's evidence? Wouldn't that be something?
Or maybe it's like VG teased to Cranston about the flash forward without giving any more info: Walter is back to protect someone. Who? Himself? Jesse? Hank? Walter looked like Walter in the flash forward--not Heisenberg.