I doubt it. Romney's screw ups happen when people push him, demand the details behind the platitudes. The debate will not offer a venue for that to happen. Romney just has to spend 90 minutes repeating conservative stock answers (taxes! national debt! defense spending cuts!) and he will avoid any moments of weakness.
We been watching the same gaffs? I've seen him choke when he tries to wing it, when he tries to say something relaxed and casual or folksy. And this is while he's just stumping.
Yes, the parties always have talking points but he's not, despite popular opinion, a robot. He's going to have to be flexible and to me that's something he's never been good at, being verbally agile. He has a problem with appearing awkward while speaking and that's something Obama, like you said, can go after without making it an outright attack. Or he'll make Romney look that much worse just by comparison, because he has composure and shows grace under fire (for the most part). I think Romney only demonstrates that when he's in control of the setting, or in control of the people he's talking at.
So yeah. I predict a lot of awkwardness from Romney that's going to just hang out there. It's the kind of thing Obama doesn't even have to attack, he just needs to stand back and watch Romney continue to get more agitated by himself. The debates aren't really about the issues, as we know as Americans. It's a televised personality contest and I feel like that's one place, barring everything else, that Romney has consistently under-delivered.