You would expect after 1000+ chapters that Oda will learn from his past mistakes but apparently he doesn't want to.
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First thing Oda needs to learn is how to have a legitimate reason for your main character to defeat the main antagonist of your story. Here you see Kishimoto creating the cause of defeating Kakuza due to Asuma's death. And Naruto defeating Pain due to Pain destroying the leaf village.
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Next step of writing shounen 101 is that when you spend over 30 chapters of your main character training, you would expect that the training will pay off.
So lets compare Naruto's wind style and sage training to Luffy.
Here is Naruto training.
And here is Naruto defeating his opponent from that training.
You see how one event follows the other? Whereas in One Piece Luffy trains for 20+ chapters and then gets two new power ups that have nothing to do with the training. Drawing shounen fights isn't rocket science. When you write a training arc, make sure you don't waste the reader's time.
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DISCLAIMER: Don't mention the Naruto war arc because everyone already knows that Kishimoto ruined that arc.