Quote Originally Posted by Yukimura
initial difficulties with learning the Fireball Technique
Initial difficulties? He learned to use the fireball technique by himself in a few days after only haven been taught the seals by his father when he was what, seven. Thats nothing like Kakashi teaching him to use chidori over the course of a month.

But it's also possible that Kishi just makes everything up with absolutely no thoughts given to plot consistency
Thats true enough. Lol, I just got it. Anyway as far as Kakashi and Sasuke goes, Kakashi also mentioned that Sasuke was a genius and managed to acquire a second element a lot earlier than most people do, which is around Jonin level.

@Abdula: Where are you getting lightning > fire from?
Nowhere its just my opinion, and I wasn't referring to relationship between the elements based on the chart. I was just suggesting that as far as the damage each element does Wind seems to be the greatest, followed by lightning, fire, earth and water.