I believe that swords can have their own will, and I think that it creates 4 distinct level of expertise in dealing with swords and will, ultimately creating four plateaus of “power”.
1.The sword and the swordsman simply exist physically, with their will being no part of the equation (Zoro at introduction)
2.“A sword follows will,” where a swordsman can make a sword become an extension of his own will (Zoro upon defeating Mr. 1)
3.The sword develops its own will, one strong enough to contend with its owners and others, becoming a Black Blade at the absolute height of this power (This is where Mihawk is and Ryuma was)
4.The Swordsman conquers the unruly will of a sword, deriving more power the more powerful the sword’s will is (This is where Zoro will end the show, surpassing Mihawk and truly becoming the world’s greatest swordsman)
Zoro has always been described as wild and bestial, and it would make sense if his Katana, being living beings themselves, would follow suit (at least narratively, if not literally). If indeed the bigger the will, the stronger the swordsman after taming it, then Zoro has a clear, compelling, and well fore-shadowed path to besting Mihawk, hopefully avoiding “but he just was stronger than him eventually, don’t worry.”
*Theory by Stovepipe032