Haha, I just beat him yesterday (I'm replaying KH2). (Beginner mode is easy, I haven't died ONCE! Well, except to Setzer, but I didn't really die. Funny thing is I beat him on Standard...)
Those back-and-forth mood swings mean that he remembers his emotions, but just doesn't know which one to use when. "True, we don't have hearts, but we remember what it was like. That's what makes up special."
"Who is this kook?"
"Remember that the Organization is made up of Nobodies."
"Oh, that's right - no hearts!"
"Oh, we do too have hearts. Don't be mad."
It's completely ridiculous that Sora's memory follows the story Nomura wanted, not actual logic. Really, in the game, he can't ever remember a thing, but after Yen Sid simply tells them that they're the ones sending the lesser Nobodies after them, he's all "You gonna cry?!" on them. I excuse most of this to Namine screwing up his heart. Trying to restore it for a year was hard enough on her, until she found out that it wasn't working, and when his whole heart was finally asleep, DiZ made her rush through 1 week, and as a result, Sora didn't really have time to get all his mental faculties back, and he had spent a long time sleeping, so his processing was much slower, and he did seem to remember making a lot of promises he never made throughought the whole game, but that was most likely because of the whole "promise" thing with Namine.
Woah, digression to the MAX.
Anyway, I found the actions against the Organization to be very stereotypical. That's why we're getting 358/2 Days - to see the "true personalities" and story of the Organization members. ^___^ YAAAAAAAAAAAY! 0_0