Great episode. Melissa McBride and Norman Reedus are both incredibly strong actors and among the few remaining originals from Season 1. I was interested in seeing how Daryl and Carol would interact given that they had been separated most of last season. I also thought the flashbacks of Carol here were effective for a change since I was annoyed last season that the show spent 2 whole episodes on the Governor, while not spending any time telling us what happened to Carol after Rick sent her away.
While I love Carol (and like Daryl to a lesser extent), I do think I would have enjoyed the episode more had it not just been followed by two weeks of bottle episodes, which I feel this show REALLY overdoes. I don't understand why this show can't handle A and B plots at the same time. Combining the three storylines from the Beth bottle, DC-bound crew, and Carol and Daryl's mission over the last 3 episodes, instead of focusing on one story at a time, would have felt a ton less stagnant. They really put a dent in the great forward momentum of the first 3 episodes by doing these bottle episodes.
I also disagree with that idea that Michonne and Maggie's development are being sacrificed for Carol. Carol got little development and barely any screentime during the first 3 seasons and was MIA for most of Season 4, while Maggie and Michonne were front and center from their very first seasons, Seasons 2 and 3, respectively. Melissa McBride is so talented, and I'm glad the showrunners are finally recognizing that, given that it's not everyday that you see a 40+ year-old woman turned into a complicated action hero on TV.