Sasuke fatally hit madara?.Getting cut in half is zero damage? This kid is a moron. Why do we bother with you. Naruto wouldn't have sealed anything if Sasuke didn't tell him to. Madara is obviously much faster than anyone par Sasuke but he did manage to fatally hit the strongest person in the manga. Saying Narutos mark left a bigger impact than being cut in half. Wow does logic stoop any lower?
There was nothing fatal about it, madara was causally chatting with Obito with half a body and giving no shits about it, Hell he was even smiling.