To answer this question, we first compare the final scores of the nine previous New Orleans Super Bowls to the other 46. The average margin of victory for games hosted in New Orleans is 19.9, appreciably larger than the average of 14.3 for all games and 12.9 for games hosted everywhere else.
But the final score can be misleading. What if we counted the amount of time each game was close? We define a close game as any time the score differential was 14 points or fewer. Once again, the games in New Orleans fare poorly: The average time spent under these "blowout" conditions is 993.7 seconds (over 16 minutes) for the nine games in New Orleans. Over all 46, the average is 687.8 seconds (over 11 minutes).
Is this a function of when New Orleans has hosted Super Bowls? Recent Super Bowls have been closer; the last nine games have only included 39 seconds where the score difference was more than 14 points. If we include only those games before that point (Super Bowl XXXVIII), the average time spent in blowouts is 854 seconds (just over 14 minutes): closer, but still a full two minutes less than New Orleans.
Lastly, let's compare New Orleans to the other two cities that have hosted the most Super Bowls: Miami (10) and Los Angeles (7, including those in Pasadena)
|City||Super Bowls||Avg. Diff||Avg. Time > 14 (s)|
Because I had to calculate the time in blowout mode by hand, I've posted the time by game to a Google spreadsheet for public consumption. Enjoy.