Honestly, I think Zoro just has better control over it now. In the King fight, it was going rampant, because Zoro had just unlocked it. But now he can control it better, so he doesn't get burned out extremely fast. I doubt we will ever see Zoro use AdCoC like he did in the King fight ever again. It's foolish to ramp your Haki up to 100, and allow it to pour out like that.