I've changed my mind.. There's AdCoC no touch and AdCoC touch..
There's some progressm, I see. Glad to hear that.
AdCoC no touch >> AdCoC touch
Possible. But I'd say it's just a matter of preference, as of now at least. I don't think you can lower your Haki level within the same version of Haki(Like, Invisible CoA, Coating, Barrier, Penetration, etc) whether you're using non-touching attacks or not. For instance, Luffy touches the collars when he removed them, and he still used the Penetration Haki:
He uses the same Haki without touching:
He kept on making contact with Kaido during the Rooftop fight:
I don't think he was pulling his punches back while attacking Kaido at least. With that being said, I think more or less the same works for CoC as well. If we're to assume all CoC based attacks that make contact are weaker than non-touching attacks, then no swordsman will ever get to use their maximum potential as they all must make contact to make cuts.