Cases are never won in the opening statement. A person should not try their case in an opening. Anything said in an opening statement which is untrue will be held against you to your excruciating regret.
Again a person does not try to win the case in an opening. They try to establish a cogent and powerful theme. So yes, maybe Romney won the opening statement. But now he must live with all those lies. Every single day, discussion about his lies. He must live with the additional theme that he will not explain any of his plans. The theme now potentially established for the debates are Romney's lies and Romney's secrets. It is likely the dominant strain to run through the campaign for the next few weeks.