Sasuke training? Name one time in shippuden sasuke trained because I honestly don't remember
He trained alone to learn the fireball technique to gain his fathers recognition which he always wanted.Proof: Learned fireball technique.
If I am not mistaken he trained himself with kunai but I cant remember, but I think Itachi or his mom may have helped him.
He trained vigorously with Kakashi to take on Gaara.Proof: Learned chidori and raised his speed.
He trained for 3 years straight with Oro so he could finally face his brother.Proof: Made the technique "Kirin" and made multiple chidori variations that unlike some else's variations they don't just change size's or color.
That is just off the top of my head.
Okay... You just said sasuke picks up things like a sponge, unlike Naruto right? Naruto learns things faster than most people. When pervy sage started training him he became stronger than sasuke.
Naruto was never really considered smart or talented, hell if you switch Naruto with Kiba J-man could probably have taught him the same things twice as fast.
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