The tension came from two basic sources: either new information to deal with (Where's Lori? Where did she go? When did she leave?) or dealing with multiple choices, all equally bad (kill the kid, cut off his leg, or grab and go). An episode like "Triggerfinger" is why episodes like "Nebraska" are so frustrating: it proves it can be done.
A lot went right this episode, including Steven Yeun absolutely knocking it out of the park, but I want to focus on one scene in particular, which gives the containment I wrote about in the previous post. It's outside, but the writing solves the problem. Carol goes to confront Daryl again. He tells her to leave. She won't. He won't leave, because it's his space, and the dead squirrels show (not tell) that he's just about gone feral again. She won't leave because she won't let him pull away. Their intent is so strong, they might as well be handcuffed together. They have to deal with each other. That's drama.
The writing is also spot on in that Daryl says the most hurtful things he can come up with. Your kid's dead. You didn't do anything. All you had to do was keep an eye on her. This man is holding nothing back, he knows what will hurt and he's using it. But she's a survivor of abuse. Not only that, she has survived the worst thing that could ever happen to a parent--the death of her child. That is a life changing experience in that you either give up entirely or decide that if you can live through the worst possible thing, you can live through anything. Some have said that Carol is an inert character, but purposefully, intentionally standing there is not inert. It is intention and it is action. You could see Melissa McBride growing roots into the ground. Daryl even uses his physicality to intimidate her and her head turn spoke volumes. The subtext there was "I'm going to get hit, but I'm not going to run." I might as well have been hit, it had such an impact on me.
So what does this mean to Daryl? He shows up at the farmhouse the next day, and gears up with the others to go to town. He and Carol have a little head nod in the house. I think that Carol is proving to be someone he can count on. Maybe not in a Shane sort of way, someone to watch your back and take out scads of zombies, but she will be there for him. He's never had anybody who is always there for him, even in his family (remember the story about being lost in the woods as a kid), and although it's taking time, he's learning what that feels like.
So much packed into that scene. Loved it. The actors cashed the check the writers wrote and it played brilliantly.