Conquers haki dominates over someone will and is not just used to knock out weak willed person their is more to it, Oda as not shown yet.
Shanks CH destroyed WB's ship.
It didn't destroy the ship but the crew mates fainted
It damaged the ship and he was not intended to use full power of CH.It didn't destroy the ship but the crew mates fainted
To be more precise, what is special about conqueror's haki