First, full disclosure: I posted this research a year ago on BTB. But I thought I might update and reprise it, given this is year 14 for Almost Andy and from what I hear Jeff Lurie has been saying, probably his last, if his last game is not a win...
I analyzed how long each SB coach took to win their first Super Bowl with their team. The bottom line is no coach has ever won the SB past his 14th season with the same team. Cowher did it in his 14th season and Landry in his 12th, no other coach has gotten in to double figures.
The 45 Super Bowls to date have been won by 28 coaches. 16 coaches won only 1, 8 won 2 (including Landry, JJ, Parcells and Lombardi), 3 have won 3 (Walsh, Gibbs, Belichick) and only Chuck Noll has won 4.
Its also been suggested that its now newer coaches that are winning Super Bowls. This has always been the case. Out of those 28 coaches, 54% won their Super Bowl in their first 3 seasons with the team. Only 3 Super Bowls have been won by coaches beyond their 6th season.
The first 14 coaches averaged 4.1 years tenure for their first win, and the next 14 averaged 4.0. So no statistically significant shift over this time (if you take the two outliers out, Landry and Cowher, these averages fall to 3.5 and 3.2 years respectively).
But there has been a big shift to "second-chance" coaches
In the first 30 years of the SB, only 1 SB winning coach won his first SB with with the second team he coached - Don Shula. (I exclude Ewbank, he won two NFL Championships with the Colts prior to taking over the Jets). And even Shula wasn't a true second-chance coach as he was not fired, but rather poached by the Dolphins (even earning them a tampering charge...)
In the last 15 years of the SB, 6 "second-chance" coaches (Shanahan, Vermeil, Belichick, Gruden, Dungy, Coughlin) have won 9 of the 15 SB's. So that is a major shift from the first 3 decades of the SB.
No coach has ever taken two different teams to a SB win, although Parcells and Holmgren took their 2nd teams to the big game. (Ewbank is the only Coach to take 2 pro football teams to Championships - getting his revenge on the man who took his job at the Colts - Don Shula.)
Will the 'first-timer" streak be broken?
The last 6 SB's have been won by first-timers - the longest streak in NFL history. (Previous longest was 5 - between Lombardi's and Shula's second wins). 6 SB winning coaches are still coaching, and 4 of them are coaching teams amongst the top 6 SB favourites. So it would seem this might be a year the streak ends.
So what does history suggest for the Eagles and the 2012 Season?
Entering his 14th season, Almost Andy is going to have to defeat history as only one Coach (Cowher) has won a SB after 14 seasons with a team (Landry getting his in his 12th season). Last year the Eagles making an uncharacteristic big push reflects some of the concern at the length of his tenue without that big win. Clearly Lurie has given Reid a mulligan for last year. However, if he survives this season without a SB win (which seems unlikely), he will be entering unchartered territory...
As to the rest of the NFC East:
The 3 first-year SB winning coaches all inherited teams with winning records. Garrett did not. On this basis, Garrett was a long shot to win the SB last year. Particularly when you consider that he had never had a full offseason to remake the team in his image and Ryan and Woicik have had limited offseasons to work their magic. But 61% of SB-winning coaches win it for the first time in their 2nd, 3rd or 4th year with the team. So he is in the optimal period to add to that statistic by 2015....
Shanahan is fighting the "No coach has ever taken two different teams to a SB win" stat but medium term may have a better chance now he has RG3. But he is a long shot this year.
[and rather than update the Giants comment, this is what I typed last year:] Based on this history lesson, there is a good chance of the first-timer streak being broken. This would suggest Coughlin has the best chance of any in NFC East of winning a SB, but my money would be on one of the other non-first time winners (Belichick, Tomlin, McCarthy or Payton).
Postscript: Something that surprised me:
Vince Lombardi only coached the Packers for 9 years, I had always assumed he coached them for much longer. But he won 5 championships in those 9 years - better than 1 every 2 years. So I guess I understand why they named the trophy after him....