I think his point was that if he said anything bad about her, she would club him over the head, like she did with the Halibut.
I agree that this was Mitt's intention with the comment - self-deprecating, haha, and a subtle slam at this 'extreme' and 'radical' lady. I can see Mitt smile at himself for this practiced response, proud at his 'cleverness'.
But just stop and think about what this says about Mitt. He's very comfortable being "afraid" of a "quote/unquote" strong, radical extremist, opponent.
Putin, Ahmadinejad, Jong Il, Chavez, Obama, Reid, Schumer, Durbin ..... would club Mitty senseless and he'd be impotent to stop it.
Just Say No to the unrepentant abortionist/statist lying political whore!