My duties on NFL Network constantly require me to comment on which teams are good and which are bad, who is playing well and who isn't, and -- most importantly -- who is going to win from one week to the next. Faced with these challenges, I'm annually reminded of Academy Award-winning screenwriter William Goldman ("Butch Cassidy and the Sundance Kid," "The Princess Bride") and his key rule to remember when trying to understand the way things work in Hollywood: "Nobody knows anything." At times, this is equally true in the NFL.
Certainly, when you look at any given team and try to size up how good it is, and how it will fare in an upcoming game, you do so knowing that there are any number of factors that can totally alter your perspective (injuries, weather, matchups or just facing an opponent that, for whatever reason, suddenly plays out of its mind, at a level not previously seen). It's not a computer simulation -- it's real life, with 53 players on each side, and a lot of room for human error and inconsistency.
For years, we've seen poorly coached, undisciplined teams show up big one week, then go missing in action the next week. What's different about the uneven performances this year is that we've seen some truly solid teams -- talented, mature clubs, led by some of the best coaches in the game -- showing the same irregular tendencies. Let's take a look at four notable examples:
Pittsburgh Steelers (6-4)
There isn't a more stable franchise in the NFL than the Steelers. Impeccable ownership, Super Bowl-winning coach, two-time champion quarterback, strong facilities and a roster of players who buy into the culture that has captured six Lombardi Trophies. Yet this team has been all over the map in terms of performance.
How do you rush for 264 yards on 34 carries (7.8 per rush) against the Carolina Panthers in Week 3, then rush for just 85 yards on 27 carries (3.1 per) against the previously winless Tampa Bay Buccaneers seven days later? The Steelers looked totally clueless while getting blown out by the Cleveland Browns -- who are better than they were last year, but still, without Josh Gordon, not a team you expect to get trampled by -- then promptly scored 30, 51 and 43 points over the next three weeks. During this stretch, Ben Roethlisberger finally adapted to Todd Haley's system and played some of the best football of his career, posting back-to-back six-touchdown games against the Colts and Ravens.
Of course, just when you think the Steelers have it together, they turn around and get beat by the one-win New York Jets. Even if you blame that loss on the weekend visit by Justin Bieber, you still can't account for the Steelers' jarring inconsistency.
San Francisco 49ers (5-4)
Entering this season, it was hard to find a more reliable contender than the 49ers. They've appeared in three straight NFC Championship Games, playing stout defense, attacking opponents with a punishing running game and relying on the unique skill set of quarterback Colin Kaepernick.
In 2014, San Francisco is still fielding one of the most physically imposing defenses in the NFL, despite missing a number of key players like NaVorro Bowman, Aldon Smith and Patrick Willis. So why has Frank Gore carried the ball 20-plus times in just two games (against Philadelphia and New Orleans, two big wins)? Kaepernick's impact on the team is even harder to figure out. Over the past seven games, he is showing signs of maturity and consistency, completing 61 percent of his passes for 245 yards per game, with 10 touchdown throws to just two interceptions. Yet the 49ers are just 4-3 over those seven games.
Cincinnati Bengals (5-3-1)
In September, the Bengals looked like one of the most dominant teams in the NFL, particularly at home. They opened the season by holding Baltimore and Atlanta below 100 yards rushing. Then they stomped Tennessee, 33-7. After a bye week, though, Cincy's defense collapsed, giving up 107 points over the next three games -- a 37-37 tie with the Panthers sandwiched between blowout losses to conference rivals New England and Indianapolis.
Through the first five games of the season, Andy Dalton looked like he was taking the next step as a quarterback, completing 68.2 percent of his passes and posting a 98.4 QB rating. But over the last four games, both of those figures have plummeted (52.3 completion percentage, 54.4 QB rating) and Dalton's thrown two touchdown passes against six picks. Yes, A.J. Green has been banged up, but he was back in the Jungle last Thursday night, when Cincinnati looked '90s-era ghastly, rolling over in a 24-3 loss to the Browns. Dalton had the sort of awful night that invites historical comparisons ("Was it as bad as Ryan Leaf's '98 start against Kansas City?"). And now you have to start wondering if this Cincinnati team -- coming off three straight playoff appearances -- has missed its window of opportunity.
San Diego Chargers (5-4)
Back in the preseason, people were saying this could be the best Chargers team in years. Mike McCoy's system was fully implemented in San Diego, Philip Rivers had re-established himself as an elite-level quarterback, Antonio Gates was healthier than he'd been in ages and the defense was revitalized. All of that looked true during the Chargers' five-game win streak. Then they were out-toughed by Kansas City, outgunned by Denver and, at a time when you'd expect them to re-establish their credentials, played their worst game of the McCoy era in a 37-0 no-show at Miami.
Have injuries hurt the Chargers' offense? Certainly, but show me a team in the NFL in November that hasn't suffered key injuries. San Diego has a two-game respite against the Raiders and Rams, but then they face what might be the toughest five-game closing stretch in the league: at Baltimore, home against the Patriots and Broncos, and on the road against the 49ers and Chiefs.
Why are so many seemingly good teams -- with quality coaching and established quarterbacks -- falling on their faces? There are no simple answers. But I think it speaks to the parity in the league. The margin for error in the modern-day NFL is so slim that even a good team can look hopeless (see: New England on Monday night in Week 4) and bad teams can rise up.
Also, scouting and game-planning is at an all-time high. What works flawlessly in September can often be anticipated and stopped come October. For teams like the Steelers, 49ers, Bengals and Chargers, the time has come to readjust and recalibrate. The teams that do that successfully will still be playing in January.
Follow Brian Billick on Twitter @coachbillick.