Sasuke knew the story in ch 646

[Young Vongola]

It just occured to me that Madara had the EMS and not the Rinnegan when he read the stone tablet's story about the God Tree and stuff. Sasuke has an EMS right now, and he was recently at the stone tablet with Orochimaru, Jugo, Suigetsu and the Kages. I think Sasuke read it, and now knows about the story of the tree, the sage's mom, etc. This could be why he was so determined on destroying the jubi and all the tailed beasts, so that nothing like that could happen again.

So now I believe he is going to be a SIGNIFICANT factor in countering the IT, or really anything dealing with the God tree. I guessed this before here:

You must be registered for see links

But now I'm even more sure

 

[Dorohedoro]

in response to your previous theory too, maybe this is why Madara keeps telling Obito he's jumping the gun... the 8 and 9 tails are still around and it may be harder to cast genjutsu on jinchuuriki that are cooperating with their bijuu since the bijuu can act as the support when it's host is stuck in a genjutsu... I like your theories though, keep up the good work!

 

[LeSauce]

I think he read it as well, he didn't really look surprised at what happened either.

 

[Brusky]

This seems to make sense

 

[Son Ryuto Uzumaki]

ok pretty neat

 

[Young Vongola]

in response to your previous theory too, maybe this is why Madara keeps telling Obito he's jumping the gun... the 8 and 9 tails are still around and it may be harder to cast genjutsu on jinchuuriki that are cooperating with their bijuu since the bijuu can act as the support when it's host is stuck in a genjutsu... I like your theories though, keep up the good work!

Thank you, sir

 

[arthurezenwanne]

Maybe........