Wouldn’t even call it unusable as is.
I am pretty sure you could cook bacon or similarly fatty stuff in there right away.
Then again there are people that see cooking bacon as a legitimate form of seasoning a pan.
If my cooking senses are right, it would be like cooking bacon in a stainless steel pan, which is sticky and burny but not impossible
No, they’re right cooking bacon is a way people season cast iron! You have to cook a lot of it though, and it’s really not the best way to do it lol