You can't learn how to bend fire from a book. [ it might come across a bit sharply, but, you can't learn bending from a book. like one can't learn how to use a sword from the written word, it's always actions — that's how zuko has learned. he could read every scroll in the palace, but he still would find himself clueless. even if he happened to be an avatar, he knows they travel the entire world to learn their craft. isn't that what his great-grandfather had done? instead of staying within the fire nation with his other great-grandfather, he had seen the world and learned it. if it could be easily gleaned from a book, he thinks the hundred year war never would've happened at all. (or, he likes to think roku would've been able to somehow talk sense into sozin). ] The writer probably doesn't even know how to light a candle.

My sister didn't learn how to bend lightning from a book. [ no, she was simply born with it. ] I tried to learn from a scroll. I couldn't even get it to clap in front of me. [ instead, it'd been with uncle that he had continued to be thrown off his feet and slammed into the earth. a scroll had taught him the truth of his heritage, confusing him even more, but it had been his actions and the tutelage of not only uncle but those he had come into contact with that had helped him discern the art of self-forgiveness. ]