Here's why USC shouldn't hire an NFL coach to replace Carroll

"Most college coaches find out it's a lot harder to coach rich 25-year-olds than it is poor 19-year-olds," Tony Dungy said on NBC on Sunday. I don't doubt that

"Most college coaches find out it's a lot harder to coach rich 25-year-olds than it is poor 19-year-olds," Tony Dungy said on NBC on Sunday.

I don't doubt that to be true. But I would also contend that most NFL-bred coaches are similarly ill-equipped to handle the unique challenges of coaching collegians.

According to various reports, USC appears ready to dip back into the pro ranks to hire Carroll's successor -- Jaguars coach Jack Del Rio and former Jets and Chiefs coach Herm Edwards reportedly topped the school's wish list after Oregon State's Mike Riley passed. (Peter reported Tuesday that Del Rio is staying in Jacksonville.) Former Bucs coach Jon Gruden is a rumored candidate as well. USC may have struck gold nine years ago when it hired former Jets and Patriots coach Carroll, but as the numbers show, Carroll, much like Jimmy Johnson, was the exception, not the norm.

The following chart shows every BCS-conference head coach hired from the NFL over the past 10 years, excluding those who had prior recent experience as an FBS head coach (Riley, Steve Spurrier, Nick Saban, Butch Davis, Rick Neuheisel and Bobby Petrino). In lieu of "playoff wins," I used "BCS berths" as the equivalent achievement.

You will not find a whole lot of success stories on this list.

If you take away the one extreme outlier in the group (Carroll), the remaining 15 coaches compiled a combined record of 408-373, for a pedestrian winning percentage of .522. Carroll and Miles were the obvious success stories (Miles left Oklahoma State for LSU in 2005), though Miles' inclusion is a bit deceiving -- prior to his three-year NFL stint, he spent 18 seasons as a college assistant. Of the 16 names on the list, 11 were eventually fired (though Jagodzinski's ouster was not performance-related).

The only other coach on the list to take a team to a BCS bowl was Notre Dame's Weis, and he's widely viewed as the textbook example of an NFL coach ill-suited for college. His Xs and Os acumen couldn't compensate for his shortcomings as a teacher and motivator, and he never seemed comfortable with the numerous non-football obligations of a college CEO.

In 2007, I talked with USC's then-offensive coordinator Steve Sarkisian about the differing skill sets involved in college and professional coaching. Sarkisian, now the head coach at Washington, spent a year with the Oakland Raiders in between his two stints under Carroll.

"The hardest part, until you deal with it, is that you're managing 110 kids, and they all have their problems and their issues, whether it's their classes or their girlfriend or not playing enough," said Sarkisian. "Not every kid's going to come in and rush for 1,000 yards. They all think they will, but for the most part it's not going to happen. How do you keep them motivated? A lot of stuff goes into that."

The most puzzling aspect of college ADs' continued infatuation with NFL coaches is that it goes almost entirely against the mold of the prototypical college-coaching icon. In nearly every case, their training took place entirely at the college level.

The following chart lists the 15 winningest active FBS coaches (minimum five years as FBS coach) and how many years they spent at each level prior to taking their first FBS head-coaching job:

Among those just missing the cut: Texas' Mack Brown, Virginia Tech's Frank Beamer and Kansas State's Bill Snyder, none of whom spent a second on an NFL sideline, either.

Carroll, it should be noted, spent 11 seasons as a college assistant prior to beginning his NFL tenure. By contrast, Del Rio, a former USC linebacker, has no prior college coaching experience; Edwards spent three seasons with San Jose State from 1987-89.

As USC AD Mike Garrett conducts his search for the next Carroll, he should take into account the possibility that there may be no other Carroll -- at least not in the pro ranks. Based on the data above, he'll be going heavily against the grain if he thinks that his next NFL hire will turn out more like Carroll than like predecessor Paul Hackett (a former NFL coordinator).

The far safer route, for him or any other AD with a future job opening, is to hire someone with significant college coaching experience. The numbers speak for themselves.