Let us face the facts of the game. Impression is what counted in the debate. Mitt improved his impression, and Obama remained the same. Mitt took full advantage of the fact that it is not what you actually say, but how you say it. The President was beat by a man who succeed in not answering a single question, but appeared to be more knowledgeable on the topic than the President. The perception of the debate was that Mitt had Barrack on the ropes for 13 out of 15 rounds.
And Barrack was stumbling, because he was not prepared for this Mitt Romney. The Mitt he was debating, was not the same Mitt Romney of the past 18 months, and none of his handlers could have known that they would create an entirely new persona. The reason Mitt appeared to know more than the President was because Mitt actually knew more than the President. No one knew what this new Mitt's policies were! He came to the debates with an entirely new campaign, that were nothing like the campaign statements of the yesterday Mitt. This is the payout for not providing any specific details, you can change them.
Change them he did! He changed them to not only encompasses the best of every policy that President Obama ever championed, but to imply that his policies would have the best of and even more. He made it seem that everything the President had accomplished was good, but his would be better. He would build upon the President's progress, adding his policies and make it even greater. He ran as the Vice President of Barrack Obama. All without giving a single detail of how he would do it, or what he would actually change.
The President loss this debate, because Mitt danced the dance better than he did. The President was fighting a spectre that never was solid, real, or even stood still.