@nik87 and
@RayanOO Your explanations are complementary imo.
I think that when Oda doesn’t really know how to end a sequence (either because he’s undecided about which path to take, or because he hasn’t had time to think it through), he relies on his two best friends since the timeskip: “hype and vibe.” That leads to this kind of situation that doesn’t make much sense in hindsight. And I think this phenomenon has been happening more and more often since Wano.
You can really feel that some plotlines are last-minute additions, with no real narrative structure set in place or clearly defined. But since Oda remains a very talented writer, he manages to get by with a few sleights of hand here and there.
As for Zoro and this Sommers thing, I imagine the sleight of hand will be to tell us that using CoC without mastery weakens Zoro’s attacks, and that, on top of that, “the omen is the opppsite of CoC” will be enough for most fans to accept it as a valid explanation.