The smirks and laughs were strictly psy-ops for the tv audience; Biden tried to make it appear that he & Raddatz were sharing some kind of insider understanding of Ryan’s inferiority, as if she was looking back at him and smirking/laughing too.
We watched C-span, only a split-screen of Ryan and Biden. Biden just looked as though he thought it was okay to smile, laugh and roll his eyes no matter what was being said. The moderator asked some good questions and some inane ones; mostly she was interrupting Ryan’s answers.