Madden's take in on par in the sense that the sloppiness and lack of attention to detail contributes to all of these close games.
The Steelers won their games by an average of 11.2 points with six of the wins being at 7 points or less (two by 3 points). Their losses were at 5.5 points per game, five by 7 points or less (3 by three points). Compare that to 2017 with wins by 9.8 ppg (eight wins by 7 or less and four by 3 or less) compared to 8.3 points in losses (three by 7 or less and two by 3 points). Last year the Steelers won almost all of their close games, but they sure do play a lot of close games. They had 11 within a touchdown in 2017 and another 11 this year. Does any team play more close games than the Steelers?
As far as some of the factors that we've discussed with losses:
Did Ben throw too much? He averaged 46.2 passes per game over the first 10 games (7-2-1) vs. 37 times per game over the final six (2-4).
How was the rushing? 109.9 yards per game in the wins vs. 49.5 in losses vs. 159 in the tie.
Penalties? 6.9 penalties per game in wins, 6.2 in losses, 12 in the tie.
Turnovers? In wins +/-0, -6 in losses, in ties -5.
What about Boswell? 7/9 (27/30 XPs) in wins, 6/10 (13/15 XPs) in losses, 0/1 (3/3 XPs) in the tie. Of course he missed a field goal in OT and one to send it to OT in Oakland. With a team that always plays with such small margin of error, having a clutch kicker is essential.