Could it be possible that the shrine scene was a flash-forward, and they are giving thanks for Walt's death? I guess that's what I was getting at with my revelation about the narcocorrido.
The clothing and the car implies, to me at least, that it occurs before their clothes-line swap & trip to Texas. So the scene doesn't seem to be a flash-forward, but more likely somewhat concurrent with Walt's activities in Albuquerque (and continuously).
I'm not familiar at all with Spanish culture and "Santa Muerte," but I wonder if that crawling scene has any real-world religious signifigance. My mind was racing (guy has his legs shot? group has their legs shot/injured? crazy drug lord orders all who come to him on all fours?) until the "reveal" of a presumably religious nature. These two cartel-mates sure are gonna be a wacky bunch. (Religion/tradition is the weapon to stop them, Walt!) With their killing of the entire truck-load of illegals, I guess they don't want anyone to know they're coming (not that the killing/truck exploding is well-hidden). Maybe they thought this "mythical Heisenberg" might've had spies on that truck, and couldn't take the chance?
I'm in the super-minority that doesn't see Walt to blame *at all* in the deaths of 166 people over Albuquerque, NM. Blaming Walt is just as valid as blaming Skyler or Jesse or Jane or cancer or whatever. There's too many degrees of seperation. Sad to say, Doug Margolis is the only legitimate person at fault, and maybe whoever okayed him working that day (and perhaps the faulty "collision radar"). A system that uses 1960s technology and can cause a tremendous mid-air collision over a major city on one person's careless mistake is seriously messed-up. Of course, the fact that Walt doesn't blame himself is proof that he in fact blames himself (obviously).
Jesse seems to have taken the "personal responsibility" thing a little too much to heart. I don't think his daughter-killing counselor (sad story) intended to have his patients accept themselves as "bad people" (just, presumably, people with faults that don't need drugs to hide them). Of course, maybe he's the secret mastermind, sending out Jesse to hook more people on meth and give him more patients. That was a high-end rehab clinic, right? It's possible that some of those people could be politician's sons/daughters, and therefore maybe a future President was in fact there.
The episode was a little slow, without much action, and just moving the storyline post-crash/seperation. I expected as much, as we've had similar eps in the past. I did expect more from a season premiere to tie-in with S1 and S2, but I can see the action coming. And we finally got the reveal from Walt to Skyler on his activities (you should've agreed on marijuana! she might've accepted that...).