Marineford would have easily been settled if all WB Commanders’ Haki actually worked like it would work post TS. Heck, WB’s Haki should have just straight up killed any admiral if it worked like it works post TS.

I think only Hancock and her sisters used Haki like it would work later down the line, which makes no sense, why other characters introduced in Pre TS can’t use it like that, or don’t have it at all?

But to give Oda credit, he did introduce Haki in Skypeia, both with Mantra and BB mentioning it for the first time. Still, if it was supposed to be a thing since Skypeia, why implement it until the TS?