One of the main complaints about previous seasons was the inconsistency in characterization between episodes. The first half of this season was notable for how often that problem was avoided. Since "Bride", however, the writers have fallen into old habits: first with the ridiculous Lana arc, and then with Chloe's decision to harbor a psychopath. This was never more obvious that in the previous episode.
The writers try to bring the season back on track with this episode, and for the most part, it's successful. Chloe's recent decisions are almost impossible to justify, even with the acknowledgment of her inner conflict between attraction and revulsion. The entire scenario feels contrived to place Chloe in a position to die, sacrificing herself to save Clark after his final battle with Doomsday.
After all, it would be too easy (and too dismissive of the character) for Chloe to die at Doomsday's hands. Instead, as this episode helps to demonstrate, it makes more sense that Chloe would try to keep Davis away from Clark and fail. It's already been said that Clark and Davis are fated to kill each other, so it's not a stretch to imagine that Clark could be mortally wounded in the process of taking Davis down. From there, it's a small step to Chloe using her healing ability (not mentioned in quite some time) to restore Clark at the cost of her life.
Still, the writers are trying to justify some of the poor characterization, and it's only partially successful. This episode shows Chloe in the midst of some serious self-delusion. When she tries to convince Clark that her actions have all been about his protection, she sounds like she's also trying to convince herself. But it still feels forced, because it's obvious that the writers are covering previous inconsistencies.
That said, it was good to see Oliver Queen back in action. Oliver should have been more prominent this season, given how he has been rather important in Clark's heroic development (as both a positive and negative example). Oliver's role as the voice of pragmatic reason in this episode is so necessary that it makes his absence in other episodes all the more glaring.
Jimmy's character arc doesnÃ¢â¬â¢t quite seem to be going anywhere yet, though his job for Oliver was kept a secret for a reason. I hope Jimmy's addiction isn't resolved too quickly; it would be all too easy to give it this barely-there treatment, which is a bit of an insult to those actually struggling with painkiller addiction. It's bad enough that Jimmy was treated like a maniac when he was exactly right about Davis from the start.