In just a few weeks, the Philadelphia Eagles will start their first training camp with their brand-spankin'-new head coach. The excitement level in Philadelphia is extremely high, because things had become stagnant under Andy Reid and Chip Kelly brings a very fresh feel to the City of Brotherly Love.
But is Kelly too fresh? Nobody really knows what to expect from the offensive mastermind from Oregon, mainly because he's never been on an NFL coaching staff before.
It's impossible to predict how things might pan out for any new coach, and that's especially the case with Kelly. He becomes just the ninth NFL head coach in the last 30 years without any experience within the league, joining this list:
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We can take the success rate of the coaches above and compare that to coaches with vast and/or limited NFL experience in order to get a better feel for Kelly's chances of making it, at least based on how history has treated coaches in similar situations.
Kelly Is a Rare Bird
Excluding those in interim roles and the seven new coaches hired this offseason, 123 head coaches have been hired for NFL jobs in the last 30 years. We compiled a database with all 123 of them, breaking them down into three categories.
The first category contained the eight inexperienced head coaches listed above, the second contained 22 head coaches who were hired or promoted despite never serving in NFL coordinator roles (the majority were positional coaches), and the third contained the 93 head coaches who were hired with backgrounds as offensive, defensive or special-teams coordinators.
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Once we broke down the stats for the coaches in those major categories, we were able to draw some conclusions linking coaching success in this era of NFL football to previous coaching experience at the pro level. 
You Might Have to Be Patient
Let's begin simply by looking at first-year success rates in order to determine how difficult it might be for Kelly to turn this franchise around overnight.
Interestingly, the most successful of the coaches from that first category started off the slowest. Johnson was 1-15 with the Dallas Cowboys in 1989. Wins were arguably handed to Switzer on a platter in 1994, while the rest of them put up mediocre inaugural seasons.
It's probably not a big surprise that coaches with NFL backgrounds have fared better during that first year transitioning into head-coaching roles. Those coaches posted a .448 winning percentage in year one, while the newbies posted a mark of .414.
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That doesn't mean there won't be some improvement after a 4-12 2012 campaign for the Eagles. The Rams improved from 4-12 to 7-9 in Brooks' first year, the Seahawks went from 6-10 to 8-8 in Erickson's first season, the Chargers were 5-11 before Riley arrived and jumped to 8-8 in his first season, and the Lions increased their win total by three with Rogers on board. Hell, even the 3-13 Oilers improved by a game in their first year under Campbell.
Just don't expect a Super Bowl run right off the bat. Only Switzer made the playoffs and posted a winning record in his first year.
Experienced coaches also fared a lot better in that category:
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Mind you, those numbers for coaches with coordinator experience could be gently inflated by what we'll call the "Switzer Effect." Keep in mind that former coordinators Jim Caldwell, Bill Callahan and George Seifert inherited Super Bowl-caliber teams, and all three managed to lead those squads to the championship in year one. Regardless, there's a clear gap.
But Will It Get Easier?
Logically, you'd think it would. But that's not necessarily the case.
When you compare first-year winning percentages to career winning percentages, you get only an eight percent increase for those coaches who entered the league with no pro experience while getting a 13 percent increase for those coaches who entered the league with at least some pro experience.
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Further, when you look strictly at playoff success, there's an obvious correlation between coordinator experience and playoff victories. Again, only two of those eight fresh-from-college head coaches have won in the playoffs, while 55 percent of those with NFL coordinator experience have at least one playoff victory. Here's a summary of the average number of playoff wins the coaches have within each category:
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Where the newbie coaches do seem to hold their own with the vets is when it comes to Super Bowl success. Thanks to two victories from Johnson and another from Switzer, 25 percent of the eight coaches from that category have made the Super Bowl (and they won all three occasions). That means those coaches won an average of 0.4 Lombardi Trophies each, which is identical to the number of coaches with previous experience (25 percent made the game at least once, with the each winning an average of 0.4 rings).Of course, that sample size is much larger, and less prone to anomaly. Strangely, the middle group of coaches consisting of those who had served on NFL staffs but never as coordinators has zero Super Bowl victories among a sample of 22.
In other words, in the last 30 years, no coach has ever gone from being strictly an NFL position coach to head coach and won the Lombardi Trophy. Active head coaches who fit that criterion and could buck that trend: Jim Harbaugh (quarterbacks coach in Oakland but never a coordinator); Greg Schiano (secondary coach in Chicago but never a coordinator); and, interestingly, Andy Reid (quarterbacks coach in Green Bay but never a coordinator).

Nope, It's Not Going to Be Easy
It's probably not going to surprise you to learn that, at the end of the day, coaches who haven't jumped straight from college have lasted longer in this league than those who have.
In this comparison, those in the first group have gone on to coach for an average of seven seasons, while those newbies have coached for fewer than five. Here's a breakdown with all three categories (we've removed all active coaches in their first five years from the sample):
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Bringing things back to that original chart, history isn't on Kelly's side.Johnson is an outlier among head coaches with no NFL background. What he did with the Cowboys in the early-1990s was amazing, and Switzer's numbers are probably inflated because he took over for Johnson only after Johnson and Jerry Jones butted heads. Every other coach on that list posted a losing record and failed to make the playoffs. And of the eight coaches listed, only Johnson and Dennis Erickson coached for more than four years.
Considering how poorly the majority of those guys fared and how much similar cases like Steve Spurrier, Bobby Petrino and Nick Saban struggled, you'd have to think that the history-based odds are stacked greatly against Kelly delivering at the NFL level.