I saw it and it's weaker than Zoro's Dragon Damnation so no need to add inferior techniques.
Also it's Ittoryu so it can only compete with Bird Dance, Shishi Sonson and Hiryu Kaen and tbh two of those are stronger than Kamusari.
Or maybe it's more fitting to 360 Pound Ho. Nothing special about Kamusari tbh, it's the simplest of the slashes. Zoro usually excels at complicated slashes that overwhelm opponents and with aCoC everything can be powerful, especially powerful in KoH. We saw how powerful Oni Giri was in KoH for example.
Kamusari is weaker than almost all zoro's attack.
shshi sonson definitely is far far superior.
an aCoC Bird Dance is easily comparable and even better cause zoro dont need to be close to his target like Roger, shanks.
people are just following the hype. By the time shanks is defeated in one strike like with Oden they will jump ship and admit Zoro is better.
They dont understand that KoH is beyond any hype.
Rayleigh stated that armemant haki is enough to hurt logia, and koh has the biggest levell armemant seen so far.
as if that isnt enought Zoro has CoC which was enough to make Ryokugyu twerk.
Zoro my using both armement and conqeror in KoH has the best level of Ap seen so far.
I say only Mihawk can surpass it cause he likely has gone through the same process to make a black blade.