As the title says, I decided to focus this topic on Mihawk and the ultimate swordsmanship challenge. Before talking about it though, i’d remind some previous events Oda focused in his manga.
Foreshadows around diamond’s durability
> At the end of the Zoro vs Daz Bones battle where Zoro ultimately managed to cut through steel, Daz Bones hinted at a future challenge (cutting diamond).
> Fast forward in Enies Lobby, Oda once again hyped the diamond durability by using it as a reference to seastone, and we know even top tiers like Big Mom begged for seastone cuffs to be removed, not to mention Shiki literally having to sacrifice his legs.
> Then later on in Marineford, Oda drew a parallel between Mihawk’s long range attack and Jozu’s diamond defense.
That moment didn’t really gave us a clear answer though, if Mihawk can actually cut diamond or not, for the simple reason that Mihawk’s attack wasn’t aimed at Jozu, but Whitebeard and it’d been mentioned that the pinacle of swordsmanship is to cut what you wants to cut depending on it’s breath.
And thus with Mihawk not aiming at cutting diamond at that point, but rather flesh(Whitebeard), it left it open if he could open it or not, especially since not only long range attacks are weaker than close range attacks in swordsmanship, but they could amplified by hardening (and in devil fruit users’s case like Jozu, it even allows you to hit the real body)