Bro, it’s higher grade swords. It wasn’t anything inherent to Shusui itself, it’s the fact that Shusui was a higher grade than what he had used previously.
I find it funny how you were talking all about how Zoro will cut Kaido because of Enma in the Kaido thread, and then now all of a sudden it’s not about the sword and all about Zoro. Stop man. Enma makes him stronger.