On top of what Tony said, I want to point out two statements in here. "threw a roundhouse kick clean on his stomach as hard as I could" "which he banged with a full swing roundhouse kick. He claimed that he was going sem contanct, simply because full contact leads to warnings, and he took that hypotethical warning" You threw a roundhouse at him as hard as you could, after you guys had agreed on semi contact. Then he threw a hard roundhouse at you in response, and you complain that he went full contact. In any dojo I've been to, that's what is expected; if you amp up the intensity, I will throw the exact shot/equivalent shot at you as a warning, then go back to the contact level we agreed on.