I personally don’t understand all the hairsplitting on here about Zoro and Elbaf, personally I think it’s just the Sanji sisters leading with their agenda and that they will shit on Zoro no matter what he does.
I think it’s totally normal for someone as unintelligent and simple as him to not realize that he used CoC against King. The man had no reference as to what CoC actually felt like, so how would he know that he used it without meaning to? I mean, he didn’t realize that he was using haki against Daz Bones in Alabasta and this is no different.
On top of that, this is a nonsensical hair to split to begin with as Zoro learning how to use his CoC is obviously exposition to help the audience understand the mechanics of it. You get a little bit from Luffy vs Kaido, some more from Zoro vs Sommers, and the rest from Sanji vs Killingham.