"Lost" recap: The simple things in life are all complicated

This week on "Lost," we got a glimpse of the non-Swan life of one John Locke, got a little more insight into the mysteries of the island, and learned why it is VERY important to throw away the used coffee filters.
Spoilers below
On a show full of frustrating characters, John Locke has always been particularly maddening. One minute he's a confident hunter with a new lease on life; the next, he's a simpering pawn in the expansive game being played by Jacob, Ben, Widmore, etc. Then, before you know it, he's dead and possessed by a smoke monster. You just can't get a handle on the guy.
Yet the Locke episodes are arguably some of "Lost's" best (witness "Walkabout" and "The Life and Death of Jeremy Bentham"). That's mainly because of the always excellent work by Terry O'Quinn, who plays all of Locke's many incarnations convincingly. In this episode, as in "LA X," we saw O'Quinn as both creepy, serene Smoke Monster Locke and as vulnerable yet tenacious non-Island Locke. Two very different characterizations, both completely nailed by O'Quinn.
I also liked this week's episode a lot more than last week's "What Kate Does." It was tighter and gave Michael Emerson his best moments so far this season (that euology at Locke's burial was classic, as was non-Island Ben's rant about the coffee filters).
It also gave us, finally, a little bit of information (though, maddeningly, just a little) about why these people are on the Island. The numbers, as it turns out, correspond to passengers on the plane. Passengers who were "candidates" to take over for Jacob and become the Island's protector. From what? Smoke Monster Locke says nothing, but do we trust him? I'm actually past guessing at this point. At any rate, here are more of my thoughts on episode four of "Lost," "The Substitute."
* Speaking of which, the title of my blog post is taken from The Who song  "Substitute." I also think it's a pretty good summation of "Lost" in general, no?
* We learn in this episode that off-Island Locke is not broken up with Katey Sagal's Helen. In fact, they're getting married. Helen also mentions Locke's dad. Does this mean that, in this version of things, Anthony Cooper isn't a complete jerk? Or maybe Anthony isn't even Locke's dad? At any rate, this seems to support some fan theories that Locke's spinal injury comes from something other than a murder attempt by his dad.
* Gotta say, when it turned out that Hurley was driving the inappropriately parked car, my heart briefly sank. I was worried that lucky, off-Island Hugo was a jerk. Surprise! He ended up helping Locke, indicating that, despite his luck, this Hurley apparently still has the good heart of Island Hurley.
* Also nice in this version? Rose, who works for Hurley's temp agency and gently dissaudes Locke from working at the construction site. Sadly, she still has cancer.
* I honestly didn't hear much of Ben's coffee filter rant. The minute I heard Michael Emerson's voice, I started laughing hysterically.
* Other great moments in Emerson vocalization: his delivery of the line "I knew him" at John's graveside. Classic.
* As for the rest of the on-Island stuff, what is Smoke Monster Locke up to? Richard is clearly terrified of him, and tells Sawyer that Smoke Locke intends to kill everyone. Is that true? And why is Richard so scared? What is Smoke Locke/the Man in Black? What did he do?
* Any guesses on who the kid is? And on why Smoke Locke and Sawyer can see him, but Richard can't? Is he young Jacob? An older Aaron? Some incarnation of the "spirit" of the island?
* So Smoke Locke could only take the form of a "candidate"? Interesting. And it supports the theory that Jacob has "claimed" Sayid, also a candidate.
* In the woods, we get another reference to "Of Mice and Men," as Sawyer explains the plot to Smoke Locke just before pointing a gun at the Locke-monster. This is a call-back to "Every Man for Himself," in which Sawyer is seen reading the book, and later discusses it with Ben.
* I noticed that all the numbers on the roof represent someone Jacob touched. But Kate isn't represented. Why? Was she a candidate, then found unworthy? Is she fated to die? Was she ever a candidate? Why isn't she up there?
* I need to rewatch the scene in the cave to see who some of the crossed out names are. Did you catch any?
* What was with Smoke Locke flipping the rock in the water? Is it my imagination, or was one rock white and one black? And was it the white rock Smokey flipped in the white? If so, is Jacob the white rock? Sigh. I don't know. Ow. Ow. Ow. Brain. Brain. Brain.
* No Matthew Fox in this episode, but Jack was present, in the form of the business card Locke labored over using. Does anyone else think that Helen ripping up the card isn't the last we've seen of the Locke-Jack connection?
* Smoke Monster Locke needs a better name. I'm thinking the Locke Mess Monster. Thoughts?