The timing of your thread is impeccable. There has been a mini-discussion in the title update thread regarding this issue and now, a developer on the team for gameplay, just as recently as Thursday or Friday weighed in on Twitter:
No momentum. Random dice rolls, think of them like roulette. Fatigue also has a bit more impact than assumed as well.
Other suggestions are to vary your play calls on offense and defense, go from zone to man to man or vice versa, call timeouts to interrupt that "momentum." When you are up by a few scores at the end of the half, don't let up on the gas pedal and get conservative.
All of us saw a Super Bowl where the Pats came back from being down by 3 or 4 scores in the second half.
That's my thoughts.