to be honest man , this is confusing.... like niblak felt that's how i felt it just doesnt seem right and there is such a thing as twisting a bit to fit your theory ... for example you say that there are steps to this Jutsu/ability but the idea of rasengan itsself is a type of jutsu that if you have fire element it could be different ,wind element obviously different so there's no steps to the jutsu....you only have to know how to mold and manipulate chakra which most shinobi's know how to do.
i get what your saying nobody is blind im just using critical thinking because to get the big picture you need to look at all the little ones first.
Didnt want to offend you, just wanted to ask for an open mind

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You need to get the little ones in order to have the bigger picture right that is true, but you need to be a bit flexible with the details too, its a manga with translations, you cant take everything to literally because of that.
If it is called a jutsu, a power or a thing even, it isnt really much of a problem.
Minato believed naruto could stop the threat for this world and he left the tools behind to do this and even helped a bit on the way, together with Kushina. He left the Key behind, so that Jiraiya could help too.
It doesnt really matter with which step they helped.
Eventually Naruto has reached an important point now.
Being able to fight this threat with the tools that were left behind.
Something Minato believed that Naruto could do (backed up a bit with Jiraiya's professy).
Minato might not have predicted every little detail, but he did know the bigger picture.
Even if Kurama told him how to transform and share it, than Kurama is just someone helping along the way. He is a tool(sounds so negative, I dont mean it like that) that Minato left for Naruto.
Minato didnt knew Bee would help, that is for sure, but Bee has helped as well, in the waterfall of truth and in the chakra tug of war.
I get what you and Niblak are feeling and saying, but in the end, what Minato left behind were tools to reach the point of stopping this threat to the world that Minato saw incomming. Being able to stop this threat is that jutsu imo and many people have helped Naruto in reaching that point.
Naruto can control Kurama his power completely now and the highest ability of that control is transforming and sharing the chakra.
The shinobi alliance is posing a threat right now to Tobi and Madara.
Anyway, I get what you are saying but I dont feel that the little details harm the bigger picture, like the name of ''that jutsu'' or Minato knowing every little detail before he died. Naruto is still achieving what minato wanted him to achieve with the tools he gave him. Stopping the threat. and Naruto is doing that with the ablity to transform and share the chakra.
It falls nicely in place with Itachi his words, how Naruto shouldnt try to do everything alone, but that he needs his comrades.
About Rasengan.
Rasengan was designed by looking at the tailed beast bomb as Bee figured out.
It doesnt matter if you have wind, fire etc.
The steps in rasengan have enabled Naruto to do Bijoubomb in human form. Bee cant do that.
No way that Naruto could have done that, without other steps like adding his elemental chakra to Rasengan. It is already hard enough to do a Rasengan. Than you have to add your element to it. Bijoubomb is even harder with yin yang chakra. It builds up in steps.
Rasengan is not something every shinobi can do, just as Sakura her monster strength is not possible for everyone.
Just as sage mode is not possible for everyone.
Konohamaru has superp chakra control apparently though.