Ken Whisenhunt spent six seasons as head coach of the Arizona Cardinals, and his tenure was really a tale of two halves. In his first three seasons, he compiled a regular-season record of 27-21, and he led the Cardinals to Super Bowl XLIII and won back-to-back NFC West titles. In his final three years, however, Whisenhunt had a combined record of 18-30 and didn't have a single above-.500 season. Here's the full rundown of his time as head coach of the Cardinals:
2008: 9-7 (lost to Pittsburgh Steelers in Super Bowl)
2009: 10-6 (lost to New Orleans Saints in divisional round)
What went wrong in the second half of Whisenhunt's tenure? It all goes back to the quarterback position. Kurt Warner retired after the 2009 season, and the Cardinals just weren't able to replace him. As noted by Revenge of the Birds, the Cardinals went through the following quarterbacks in the post-Warner portion of Whisenhunt's tenure as head coach: Matt Leinart, Derek Anderson, Max Hall, Rich Bartel, John Skelton, Kevin Kolb, Ryan Lindley and Brian Hoyer. There's not exactly much talent on that list, and Whisenhunt wasn't able to develop anybody on that list into a winning quarterback.
Whisenhunt's tenure in Arizona ended on a pretty sour note with the Cardinals following up a 4-0 start to the 2012 season with a 1-11 finish. The Cardinals' only win in their final 12 games came against the Detroit Lions, which are now considering Whisenhunt as a candidate to replace Jim Schwartz, who was fired after overseeing collapses down the stretch in each of his final two seasons in the Motor City.
The final three years of Whisenhunt's time in Arizona may have been ugly, but when he had Warner as his quarterback, he made a lot of history for the Cardinals as a franchise. For starters, he led the Cardinals to their first ever Super Bowl, and he had more playoff appearances (2008 and 2009) in his first three years than the Cardinals had in the past 24 seasons combined. Also, according to his bio with the San Diego Chargers, Whisenhunt "became the first Cardinals coach to go .500 or better in his first three seasons with the team."
Perhaps the most impressive stat about Whisenhunt's tenure in Arizona is this: Before he was hired, the Cardinals were riding a streak of eight straight losing seasons. The Cardinals went 6-10, 3-13, 7-9, 5-11, 4-12, 6-10, 5-11 and 5-11 before Whisenhunt's arrival. After Whisenhunt's arrival, the Cardinals had three straight .500 or better seasons and won at least eight games in four of his six seasons with the team. The Lions, by comparison, won more than seven games only once under Schwartz.
It's really hard to judge what Whisenhunt did in Arizona given how up his tenure was from 2007-09 and how down it was from 2010-12. His success was certainly linked to Warner, but it's not like Warner was exactly lighting the world on fire prior to Whisenhunt becoming head coach. The arrival of Whisenhunt helped Warner turn his career around, and Whisenhunt's downfall was not being able to replicate that with any of his other quarterbacks.
It's really impossible to predict what Whisenhunt will do in Detroit if he is hired as the next Lions head coach. Every situation is different, and there are various factors that go into being a successful NFL head coach. Whisenhunt's track record suggests that winning seasons, playoff runs and the Lions' first ever Super Bowl appearance could happen if Matthew Stafford can play like Warner did in his final few years. At the same time, though, Whisenhunt's track record also suggests that it could be more of the same for the Lions if there are issues at the quarterback position.
At the end of the day, there's simply no telling what will happen if the Lions hire Whisenhunt, and the same goes for other candidates as well. Just because a coach won with one team doesn't mean he will be successful with another, and just because a coach lost with one team doesn't mean he will continue losing with another. Every coach has his flaws, and everybody in the mix for a head coaching job has some track record of success. For Whisenhunt, his track record is highlighted by turning around a perennial loser and taking them to their first ever Super Bowl. He followed that up with a rough few seasons as his tenure in Arizona came to a close, but I think most Lions fans would take something similar in Detroit if it meant finally reaching the Super Bowl.