I think Romo takes a series or two to get "in the flow." Maybe a little too hyped so he tries to aim the ball with the extra adrenaline flow and then after the first series or two settles down.
As far as yesterday in particular, I have to say that I really wasn't surprised that TB scored on their first possession because I felt like it was the "let down" that comes after a big victory. But, I also felt like we would bounce back, unlike previous recent years where that would've set the tone for the game.
This team has, I believe, the legitimate confidence that comes when you know that if you play your game, you will not get beat. I think they have started to cross over into that magical realm where you "expect" to win.