What do you want to Proof? Even when Ninjutsu workd they heal it away like nothing omg let it be this is now not importend
it took chapters until they understand that only Senjutsu/Taijutsu works ....and this should be for nothing ? NOOOOOOO IT IS MANGAFACT ^^
Even when Senjutsu hit him, he healed right away, your point being? Even when their bodies are blown apart, they heal almost instantly. Senjutsu and Ninjutsu does the same amount of damage to their bodies, shown when Obito is first hit by a non-Senjutsu Rasengan and a Senjutsu Rasengan. The reason they said Taijutsu and Senjutsu was the only way was because the Jin cannot neglect it using the black chakra like he can with Ninjutsu.
You don't try to beat water with fire, as that would be pointless as water itself is almost immune to fire. Same logic applies to the Juubi's Jin. Because of the Black Chakra, they are almost immune to Ninjutsu, but their bodies can still take the damage if someone is fast enough to deal a direct hit.