IF WALT IS THE MAN WHO KNOCKS AND SKYLER IS THE WOMAN WHO KNOCKS, DOES WALTER JUNIOR GET TO BE THE JUNIOR WHO KNOCKS? It doesn't seem right to let the return of Breaking Bad go unremarked.
Skyler is struggling to get a grip on the fact that her husband is a terrifying sociopath, but just when we're in danger of feeling some sympathy for her, she is forced to remind us (and herself) that other people see her in exactly the same way. And that's one situation that she can't blame on Walt -- both the cause and effect are hers alone.
Meanwhile, Walt is not just confident; he's showing off. He shows not a trace of fear during the meet with Mike (leaving Jesse to scramble to defuse the situation) because he is so sure that Mike will recognize that their interests are aligned. He doubles the battery array for the magnet (does this increase the power in a linear or exponential way? I don't know), not because he has to, but because he wants to feel the power, and he doesn't bother testing the juiced-up magnet. He doesn't just leave the truck; he wants to leave the truck, to demonstrate his utter confidence at having left no trace of himself. This is not the cautious Walter White of the first couple of seasons, obsessing over every detail, fussing over every tolerance. His cleanup of the bomb-making materials is haphazard; his disposal of the lily of the valley only an afterthought. This is a man whose high opinion of his superiority is turning into a belief in his invincibility.
And that's in contrast to Hank, who slowly and thoughtfully works his way through the shell of the cook lab, emphasizing that he and Walter have switched places. It doesn't matter that his careful observance didn't pan out this time. Walter used to be the meticulous, quiet one; Hank was the loudmouth who relied upon bravado instead of competence. Now it's Hank who has slowed down (and it's no coincidence that the catalyst for this change was his watching a tortoise cross the desert bearing the head of Tortuga), and it's Walt who's going to get caught napping.
Random note #1: this episode seemed a little sloppy from a plausibility standpoint. Wouldn't a magnet that strong rip the truck body and engine apart? It seems unlikely to me that a truck like that -- even with an aluminum and plywood cargo bed -- wouldn't have any ferrous metals. Also, it seems unlike Gus Fring to just leave a laptop with all of his crime video laying around.
Random note #2: The plot, and Jesse's "hell yeah, bitch, magnets!" -- this is just a pop-culture reference to ICP's "fucking magnets, how do they work?," right? (That's right, second ICP reference in one day.)