I disagree. How was Kushina able to comoletely seal the Kyuubi into her, then? Minato said it was impossible for HIM.
But I do think that Hagoromo's brother was the Uzumaki ancestor. Could we say that it was a combination of Hagoromo and his brother who developed the sealing technique for Jinchuuriki?
And sealing half and half would imply that the Hago bros are weaker than Madara or Obito, who had greater portions of the Juubi inside them. I doubt that's the case. How would Hagoromo have been able to use Creation of all Things? Why aren't there two Juubis running around?
I like the premise here but there would be too many discrepanicies.
Minato stated it was impossible to seal away the entire Kyuubi via the Reaper Death Seal, Kushina "sealed" Kurama within her as a jinchuuriki. They're two different things.
I also believe Hagoromo and his brother were in coalition to make the sealing techniques.
As I stated with while conversing with Waltz; each brother sealed 50% of the Juubi within themselves.
If anything, Obito and Madara would be weaker then each brother as they are Jinchuuriki's from a portion of Hagoromo's half. (Go back and read those if you want the percentages)
Hagoromo would still be able to use Creation of All things. Madara was able to manifest his will while near his death, Hagoromo was beyond a human once he became the Juubi's jinchuuriki. In fact Darui was skeptical until Obito assured that he was capable of doing amazing things once he became the Jinchuuriki (Chibaku Tensei the size of the moon for example) [left side of this image is the important part]
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More than that, Obito himself stated he cannot be judged by the likes of Tobirama's perception once ascending as a jinchuuriki.
There aren't 2 juubis running around because as I stated in my Original Post; the other was kept secret and hidden away.
I'm glad you liked the premise, and hey can't please everybody
