Board Thread:Naruto Discussions/@comment-25122992-20170428150337/@comment-4961229-20170503190150

If Kabuto had employed this possibility of nested Edo Tensei, it would've been an unstoppable jutsu. Kabuto could've performed Edo Tensei on several people, then had those people perform Edo Tensei again to summon sets of other Edos. Even if you stopped Kabuto and forced him to stop the Edo, it would only stop the middle men. If you weren't careful to get all the info on how to stop everything, you might end up creating nearly unstoppable Edos that only someone like Hagoromo could send back to the pure world.

Itachi actually would've fell victim to this. All he orders Kabuto to do is "teach me the seal capable of stopping Edo Tensei." Kabuto tells him the necessary hand seals and he remarks, " that's all of them." Then he has Kabuto perform them. If Kabuto had done what I suggest, Edos would've still been running around till Christmas of next year. And there's nothing that could be done except Hagoromo, battlefield therapy sessions, and sealing them away.