Board Thread:Naruto Discussions/@comment-25531508-20140923043228/@comment-22985334-20140925211612

Dan was the one who said Madara could only be stopped by Hashirama. Since he was dead he wouldn't know how old Hiruzen had gotten, and because of when he was alive he would actually have a better understanding of how strong the Senju brothers were instead of someone like Iruka.