A couple of people in the bunk were talking briefly about 5cm/s yesterday (didn't join in the conversation just kinda overheard it) while I was thinking about some other things myself, and the two just kind of came together and made me think about the film once more, in particular about the third episode.
The third episode is often not as well received as the first two, it seemed kind of shoddy or perhaps rushed. A music video with a summary of events more than an actual story. Yet I'd beg to differ. I feel that the third episode makes a strong point of its own, and the flashbacks were a necessity to create this effect.
The key point in this scene was Takaki’s smile at the end and answering the question of why he did so is the key in understanding episode 3. Some interpretations include that he was thinking of fond memories, some say its because in that one moment he suddenly finally was able to move on. I think both are too simplified and fail to grasp the complexity of the emotions in this character.
I'd say that he didn't smile because he was suddenly able to overcome his feelings, nor because he was dreaming of old fond memories. He has been learning to let go, to move on, and knows he has to do it, but she had inevitably become such an intergral part of his life that he couldn't really do so.
At the point when the train blocked his view, he remembered their promise, at the train station, watching cherry blossoms fall, he wondered if it was really her that he saw, at this destined place where they promised to meet. When the train passed and she wasn't there, he felt it in his heart that it didn't really matter if it was really her. He accepts that they were no longer a part of each other's lives, even if the prints she left on his heart will always remain there. It wasn't something new to him, he wasn't suddenly able to be free of his emotional turmoils, but it was a moment of carthasis where what he knew was aligned with what he felt in his heart. In that brief bittersweet moment, he knew it was going to be alright.
I was reading some articles about other people's perspectives on 5cm/s. The first episode would be the most straightforward with little variation in interpretation. I noted that the second one had some strands which weren't too obvious in the first look though. I think its rather poignant to note that in the second episode, Takaki and Akari had stopped communicating with one another, and that Akari in Takaki's world had become more of someone of his own construct built from his hopes and his memories, than a real person.
Interesting reads, including some of the comments: