Actually, I think I understand where Romney is coming from. He's under pressure from a lot of people who think that he's too wishy-washy, having held more liberal views in the past, but claiming now to be a conservative. His healthcare policies have been linked to the one used by President Obama, and the conservatives hate Obama Care(tm). Recently, Romney lost his front-runner status again, and he probably thinks the best way to do that is show some ballsack at some point.
So he picked some question and decided to power-play the hell out of it, so the news would have a soundbyte/clip showing him being a badass. For conservative Republicans, it just might be effective, as a display of power and strength is what they appear to admire in a candidate.
Am I saying it makes me like him? Hell no. But it might work out to his favor anyway.