@bold1\i am not underestmating harmons buddy it can heal and increase the power and all that but my point is it cant reattach if he got cut so the healing thing dsnt have much of a thing here cause zoro is able of cutting him let`s take luffy`s red hawk it will damage him hard and make him unable to fight (assumption) he can inject his body with harmons to recover but if zoro cut him completly (somthing he can do ) harmons cant help cause he dies instantly and no harmon can reattach him
2\zoro is fighting with his sowrd and before time skip he has the best reaction speed among the crew and now he has CoO so the possibility of getting touch is low-u don't think he can just dodge them.
3\ equally ? i dont recall that-ivankov was able to injure kuma.kuma wasn't able to land a single blow on ivankov.
4\ he did`nt show any haki (i am not saying he dosnt have haki but since he didnt show it cant be counted )-he hit akainy multile times and even had knowledge of conquer es
ivankov can afford to take multiple slashes from zoro.he inject himself with hormones that temporarily reduces pain.but with one touch on zoro and some hormones he can tottaly destroy zoro.like i explained earlier like ivankov can't reattach himself after being cut zoro can't battle after getting hormones injeceted in.any hormone will for example something like Adrenaline. it can cause:Raises blood sugar levels by stimulating the liver to change glycogen into glucose
Causes fatty tissue to release fat into the blood
Increases the heart rate
Increases blood flow to the muscles
Reduces blood flow to the skin and the intestines
Widens the bronchioles
Dilates the pupils
well if all thees things happens to some one in a battle they are done for