Skills before Jiraiya's training:
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Skills after Jiraiya's training:
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This. Naruto had to improve his basic skills before doiing anything else. If he didn't, then his other abilities wouldn't be as good since his base form was lacking.
Didnt teach naruto jack.
Taught him how to fail at breaking genjutsu, or to run away from genjutsu users. Also taught naruto that in order to make a bigger rasengan, that all he needs to do is pump more chakra into it. As if that wasnt obvious.
He shoulda taught Naruto senjutsu, or at least taught him more about the toads he has at his disposal that he can use in battle. Didnt even teach naruto which element he has. Funny thing is that jiraya taught the ame orphans more in a shorter time than naruto had. And those 3 knew nothing about being a ninja, never went academy, so they had to learn from scratch. Didnt teach minato anything except summoning jutsu either. In fact minato taught jiraya.
Hes a weird teacher.
Except all the konaha 11 rose significantly over the time skip. Its just natural, they all got older, therefore wiser, stronger etc. Naruto didnt accomplish anything that he couldnt have achieved with Kakashi in the leaf for 3 years.
You don't know much about the art of combat, do you?
It's all well and good teaching Naruto an array of powerful techniques, but if his skills are unrefined, they'll be useless. Jiraiya had Naruto polish his skills up to a good standard.
He also taught him Ōdama Rasengan and Kaifū no Jutsu to supplement his newly refined skills.