Board Thread:Theories and Speculation/@comment-28464629-20160515105435/@comment-5407586-20160515200232

Legendary Super Saiya-Jin 4 wrote: Madara was an incomplete Ten-Tails' Jinchuriki (unlike Hagoromo), and Kaguya was absorbing the power of everyone across the world when she resurfaced due to the Infinite Tsukuyomi. Which would've logically made her stronger than she was before. The Rinne Sharingan is also only used for Amenominaka and Infinite Tsukuyomi according the wiki, it doesn't increase your power. Even so, I still think Hagoromo meant it when he said that Kaguya was stronger than anyone, including himself as the Ten-Tails' jinchūriki.