User blog comment:B214/Question and Answers 4/@comment-116.75.186.9-20150129133639/@comment-16281343-20150129134237

Don't know. Kusanagi Sword's abilities as a holy sword wasn't showcased. It became more of it just being a vessel of Yamata no Orochi's soul.

Though at the last part, Kusanagi Sword + YnO acted like a SG where it responded to the user. But that can also be said with other holy swords.

Then there's Durandal's ability of cutting anything, even Rias' Extinguis Star. So, ¯\_(ツ)_/¯