I don't think he pulled it off but Groves could have made an impact with that silent stare, "I'm in disbelief Carl... You... Actually... Think... You're the better fighter... Astonishing."
Groves came across like a clown in that video. Clearly when things go off script he can't think fast enough. Those silences were embarrassingly like a 7 year old child "of course I could answer the question, but I'm not going to to, why should I" err because you're in a pre-fight QA session... LOL what a plum.