That's because tsunade uses her soulin the White seal jutsu, that's why her life span shortens with each use, it makes her punches more powerful and Raikage enhances his speed with Lightning transmission armour and even then, Tsunade was noted to be fast as Raikage without V2 armour, which is pretty interesting if you ask me. Raikage by that time was lightened by Onoki which only means Madara was saying Lightened A >> Tsunade in speed, V2 A slightly greater or equal to tsunade! Kishimoto was nice enough to hype tsunade's speed despite her not having a name for herself in the realm of speed. I think kishimoto is a fair guy in that aspect, the feminism stayed back in part 1 to be honest.