Some of her behavior kind of makes sense through a lens of "She was angry that Saul was still sticking to the plan" but not all of it. The plan itself was kind of ridiculous as well, because if Dar had snatched her up, it'd be blown. If the guy on the phone (I forget his name; The surveillance guy) doesn't say "say hi to your mother" the plan is blown. The chances of it working at all were so slim that doing that to Carrie makes no sense.
I can imagine a scenario where she's forced into it because Saul knows about Brody's northern escape and threatens to expose her. He's basically mindfucking her at this point if that's the case. That's not how it seemed though...it seemed like she helped formulate the plan.
I forgot about those parts, yeah it just adds to how stupid the twist is. This is literally like one those "twists" in 24 where their is a mole in CTU or something. Where the actions a character makes before the twist is revealed make no sense once you learn of the twist. And, usually on top of this their entire demeanor and attitude changes once the twist is revealed. Terrible.
Also, I've also made it a policy to skip all Dana/Brody family scenes so I'm just wondering if I missed anything slightly important? I did notice Mike was back.