What the heck!

Well it's not like the two never saw each other after the tournament; they still had another 6 months of their senior year left. The fact that Johnny handed him the trophy while saying "You're alright LaRusso, good match!" demonstrated that Daniel had earned Johnny's respect. Not to mention Miyagi saved Johnny from a beating in the parking lot after the tournament. I always imagined they went through the rest of their senior year being civil when they were in each other's presence but never being friends. After 30 years it makes pretty good sense that an old rivalry in high school may seem silly so I thought it was pretty cool for Daniel to greet him like that.

If you have watched the original movies, you'd know that Daniel is a naive but well-meaning kind of guy, so I am not at all surprised that he greeted him the way he did.

I was more surprised about the kick in the head comment, that's not very Daniel'ish, but then again, he is older, people do change a bit over time.

- Seeing Daniel's family, I can understand that he may have developed a sour edge over time :P