We're not, actually. We tied for ninth in the league last season in offensive touchdowns in the first 10 minutes of the game. (The eight teams ahead of us were the Bills, Falcons, Giants, Packers, Panthers, Patriots, Saints and Texans.) Romo does tend to start slowly, though. (His career first-quarter passer rating is 79.1, and he is over 100.0 in every other quarter, including overtime.)
I would say more like 99%. I think it's a huge advantage to have the ball late in the second quarter knowing that you'll also get the ball to start the third. You could get back-to-back scores (like we did against the Giants) and take control of the game. Or you could use the clock and ensure that the opponent doesn't get enough time to score before halftime, knowing that you'll get the ball right back after halftime. If you have to kick off to start the second half, you don't have that luxury.
Against Seattle, it would have been especially better to defer so that the Seahawks have to put their weaker unit on the field first. And in case nobody on our staff noticed, the Seattle crowd is quiet when their offense is on the field. Stupidly choosing to receive meant that the Seahawks got to use their two biggest strengths right away -- their defense and their crowd.