Mitt Romney firmly stood his ground in Las Vegas as his Republican rivals tried to pound him, humiliate him and drown him out.His reward: A spate of headlines saying “Romney Loses His Cool,” including one in The Daily Beast.I think that’s wrong, and here’s why. Yes, Romney got a bit agitated in Tuesday’s debate as Rick Perry, Rick Santorum and Newt Gingrich ganged up on him, especially when the first two wouldn’t allow him to utter a full sentence in reply. At one point he seemed exasperated when he told Perry: “You have a problem with allowing someone to finish speaking.”Yes, Romney probably shouldn’t have invaded Perry’s space by placing a hand on his shoulder. And yes, Romney shouldn’t have said “Anderson?” in hopes that the CNN moderator would cut off Perry for what was a blatant violation of the rules.But here’s the takeaway. Romney’s Achilles heel is that he can come off like a brainy accountant who never breaks a sweat. The wave of attacks at the CNN debate, and his heated attempts to push back, made him seem, well, all too human. A few hairs might have fallen out of place. He had a chance to show a bit of passion, and Americans like that in a leader.Now maybe I’m wrong. Here’s what veteran GOP consultant Don Sipple told me: “Romney’s mega-problem is that he’s fairly unlikable bordering on annoying. You don’t get a sense of warmth from the guy.”Did the debate help that? “I don’t think he rose above the rancor—he was part of it,” Sipple says.And much of the punditry tended toward that view.“It was Romney’s worst debate so far,” says National Review Editor Rich Lowry, “if only because his opponents finally delved a little deeper on Romneycare and for the first time ever he showed anger in public… And Romney came off as a little frantic and maybe too much of a hall monitor about the debate rules.”"Romney got rattled on stage, and everyone knew it,” writes Hot Air’s Ed Morrissey. “He lost his temper, raised his voice, and looked decidedly uncool in his efforts to push back on immigration — a topic which Romney used in earlier debates as a club against Perry.”“Perry clearly got under his skin in a way that no other candidate has this year, and it showed,” says Salon’s Steve Kornacki. At one point, “Romney looked red-faced and almost unhinged.”Unhinged? I think these descriptions are way overstated, but hey, debate scorecards are inherently subjective. There was also a rough consensus that Perry didn’t help himself, that his attacks on, for instance, a 4-year-old report that Romney’s lawn company employed illegal immigrants came off as overbearing.That was the focus in the post-debate spin room. “I think Romney did come across as petulant," Perry spokesman Ray Sullivan told reporters. Romney spokesman Eric Fehrnstrom called Perry “desperate,” saying that “Rick Perry had a strategy of coming into this debate to kill Mitt, and he ended up killing himself.”Maybe all this will be forgotten by next week. But you don’t win a presidential nomination without getting roughed up a bit, and Romney has now demonstrated that he’s comfortable with combat—even if he did get somewhat ticked off.