Once again I see a fan doesn't understand how time works One piece. You can't determine how much time has went by just by the number chapters
You can't determine how much time has with by just by the number chapters were released between the time a battle started and ended. Especially when you have flashback chapters. Are you saying Zoro fought Lucci years before either one was born Kuma was a child?
Perfect example of someone who doesn't understand the manga and Zoro's fighting style.
It's not about whether he use 1,2, or 3 swords. It's about the number of swords he used the majority of the time.
When Zoro faced BM, Kaido and King he used 3 swords the majority of the time. If Zoro use a different number of swords it was just perform a technique. Afterwards you went right back to using 3 swords.
Zoro has used 2 swords the majority of the time against Lucci. That no different than his battle against Hody , Monet, Pica, Hawkins, Drake, Killer and Apoo.
The number of swords he used the majority of the time tells us the battle difficulty.