I say anything is possible so this thread could very well be true, remember when no one thought tobi was obito and everyone had egg on their faces afterwards, and how people didn't think madara was in the last Edo coffin, Orochimaru was supposedly dead and lost and the 4th hokage couldn't be brought back by Edo tensei. I'll agree that he could be comparing Sasuke to the so6p or I'll take it a step further. The tailed beast are all chakras monsters right, now we all see with madara that the rinnegan can be turned on and off. Heres a bigger speculation people might disagree with but hell i was right on everything else in Naruto so far...
If the so6p was the CREATOR of ninjutsu he had to have no real power at the beginning. Which family in the narutoverse has strong occular jutsu and a strong body... That's right the hyuga. Do you see the extreme strain the byukugan puts on the user, and look at what the hyuga can do with their chakra control. Damn near the same thing as the First hokage, Tsunade and Sakura. I think as an hyuga type of fighter he took on the 10 tails and when pushed to the limit his byukugan transformed to the rinnegan and he gained power thus creating his own powers, then in sealing and seperating the 10 Tails, you get all the chakra natures found in naurto and each beast was able to teach him and others their individual skills because they were friendly. Earth, wind, fire, lightning, water, lava, poison, scorch and the evasive substitution techniques, anything they could do they taught. Also the hyuga do have power sealing techniques. And lastly if you take the rinnegan purple and take out the deep red color of the sharing an you're left wit the light blue tinted color of the byukugan. Light byukugan represents purity and love, sharingan represents hatred and revenge, 2 paths to the rinnegan.