Ahh, I still remember my first time playing the game, when I didn't quite understand the Sphere Grid. I just went through the grid just to learn the abilities, and I completely ignored the attribute nodes. XD I got as far as the big Mana Beam Turret thingy Brother uses against the party.

But yeah, the Sphere Grid is very important throughout the game. That's why it's important not to skip through the tutorials. Whether you did or didn't, I may never know. But you should get to know the Sphere Grid. There aren't any of those stalls with the tutorials in the Moonflow, so you should start a new game and pay close attention to Rikku's explanation of the Sphere Grid.