BS. I totally disagree. Being above the bell curve on the number of close games you should statistically win is a sign of good coaching. Blowouts are a sign of a talent advantage. Blowing everyone out (1995) is a sign of great talent and great coaching.
There are 4 possible outcomes in a game...
1. Lose by more than one score
2. Win by more than one score
3. Lose/Win by less than one score.
Good coaching doesn't create a preference for any of these. Good coaching is as likely to create a close game that you lose rather than lose a blowout vs. allow a team to win a close game. There are so many factors that determine an outcome...who is hurt, the talent differential, the schemes, home field, the weather, and good coaching can lead to a blowout win, a close win, a close loss, or even a perceived less of a blowout. Good coaching will eventually lead to a talent differential, or more efficient use of talent, which will lead to more two score wins...ie Minnesota blowing out their last 4 opponents, but it doesn't lead to more close wins any more than it leads to more close losses. I appreciate there may be a very slight clutch factor at the very highest level of football, when players have been doing it for a decade but a sport with 22 moving parts on every play...over 150 plays, on a field exposed to environment conditions using an oblong ball doesn't leave much room for clutch.