And I doubt shikaku knows how powerful the juubi is. If naruto in sage mode can't measure the true power of the juubi then I don't think the HQ can. The alliance has still a change to beat the juubi/madara. Well, it depends on naruto. If he's going to stop acting like a bitch then he knows what he should do. Just like I said, naruto possess one of the strongest summons in the ninja world. Yea, I'm kinda hopin' that ma and pa will enter that war and kick naruto's ass.
The only one who can think of a brilliant strategy/plan on how to defeat a sage is a sage. That's why for me, ma and pa are needed in the battle field to think of an strategy on how to defeat the juubi. Both of them are sages who knows so much about the natural energy than shikaku, and maybe they possess a powerful jutsu that's more powerful than the alliance jutsu. In fact, maybe their ultimate genjutsu is more brilliant to use as plan to stop the juubi's movement. And I doubt both madara and obito can escape on that genjutsu.
This man just drove the manga into the ground. Now someone without much of any information on how Juubi can be stopped has come up with a legendary hind-quarters pull that will be the final nail in the coffin of this Manga's declining credibility and poor writing. You disappoint me, Kishimoto.