Philadelphia's collapse under coach Chip Kelly this season was, if not entirely predictable, at least familiar.
It fits a pattern we have seen over and over again with NFL head coaches who don't intern first as an assistant coach in the league.
Those screaming at their TV at home might not believe this, but the job really is tougher than it looks.
In the last half-century, Johnson - winner of two Super Bowls - is by far the most successful coach who came into the NFL as a head coach without previous experience in the league. His only competition would be Minnesota's Bud Grant, who had 10 years experience as a head coach in Canada before taking the Vikings to four NFC titles but no Super Bowl victories.
Only two other coaches have taken a team to a Super Bowl without previous NFL experience - Barry Switzer, who took over Johnson's team, and Hank Stram, the first coach of the Kansas City Chiefs.
There is no indication that Kelly, whose Eagles have gotten progressively worse during his three-year reign, is about to join that list.
He was hot two years ago when he started with the Eagles.
He was fresh, he was new, he was going to radicalize the game with his fast-paced offense. Fits a pattern.
Whenever a coach has the slightest touch of success with a new approach in the NFL, there are always people acting like he just split the atom for the first time, and that the game was about to be changed.
Remember Mouse Davis? Whatever became of the run 'n shoot?
Remember when everyone thought running quarterbacks like Michael Vick would be the next big wave? Yes, Russell Wilson can run a little. But he also has a higher pass completion percentage than Tom Brady, Carson Palmer, Aaron Rodgers or Andy Dalton.
The bottom line is very clear.
Two major innovations that shook up the league in recent decades were the West Coast offense (Bill Walsh) and the zone blitz (Dick LeBeau). Otherwise, there really is very little new that succeeds in pro football. We might have some different emphasis, but teams still win championships with dropback passers and strong defenses.
For the third consecutive season, Kelly's Eagles are the only team in the league averaging under 27 minutes time of possession per game, which means that over the course of a 16-game season, their defense spends an hour and a half more on the field than their offense. That is not a formula for success.
Yet, owner Jeffrey Lurie was entranced by Kelly, enough so that he took a second run at him after being turned down the first time because Kelly wanted more control over personnel. He finally got it this year, and how has that worked out?
Mike Holmgren, one of the six coaches who took two franchises to the Super Bowl, once explained the difference between coaching in college and coaching in the NFL.
College players, Holmgren said, are "worried about classes and their scholarships, and then looking forward to the NFL in some cases, and what you say goes. I don't think it's ever that easy in (the NFL)."
It really isn't.
You may not remember all these names, especially if you follow the NFL and not college football, but consider some of the failures - Bobby Petrino, Lou Holtz, Butch Davis, Steve Spurrier, even Nick Saban (who had been an NFL assistant before becoming a head coach in college).
"In college, you have control of who you get, you have control of your whole situation football-wise - your recruiting, your travel, everything," explained Dennis Erickson, who won two national championships in college but flopped with two NFL teams.
"When you get into the NFL, that's not the case."
Said Holmgren: "The old way, 'my way or the highway,' that worked in high school or college to a certain extent, doesn't have much oomph to a guy who just signed a five-year, $60 million contract."
After Spurrier failed as the Washington Redskins coach and returned to coaching in college, he was asked what he had learned in his NFL gig.
"Humility," he said.
--Ira Miller is an award-winning sportswriter who has covered the National Football League for more than four decades and is a member of the Pro Football Hall of Fame Selection Committee. He is a national columnist for The Sports Xchange.