-Minato's jutsu, as awesome as he tried to make it out to be, would not have worked on the Juubi, since well, Minato doesn't use Senjutsu.
-It's absolutely not possible that the Yin portion of the Kyuubi's chakra yielded no increase in Minato's attributes once going into his cloaked form. Like hell, if it didn't, why even go into that form? It's practically identical to Naruto's 1st cloaked state. When Naruto goes into it, his speed, power, and chakra increases. The same should apply to Minato. Minato just isn't running circles and taking mad shits on Juubito because apparently, Juubito is turning out to be the end boss.
-Minato isn't holding back, there's just not much he could do by himself. If he was holding back, wouldn't he be kicking himself for it, like Sarutobi did when he could have offed Orochimaru while Orochimaru was still wet behind the ears and Sarutobi was more in his prime? Minato was reflecting on his previous thoughts of Obito and if it distracted Minato (though no proof that it would have made any difference if he was more dialed in), that’s knock on him for not being as focused but to go as far as to say he is deliberately holding back is unheard of at this point.
The Specialist, forever
^My first thread.lol