I’ll be spending the weekend in Cortland, New York, covering Jets training camp. The big story there, of course, will be how the Mark Sanchez/Tim Tebow drama unfolds. The party line among media members is that the duo is doomed to fail, because a team with two quarterbacks doesn’t have one.

Last year, Mark Sanchez ranked 27th in Net Yards per Attempt, so the Jets were behind the 8-ball at the quarterback position well before the Tebow trade. Not that he’ll necessarily help things: Tebow averaged even fewer net yards per attempt than Sanchez in 2011, although arguably his numbers should be viewed in a more positive light.

In my view, the Tebow trade simply gives the Jets more chances to succeed, not unlike when a team throws multiple late round picks at the same position. The most tired complaint regarding the situation is that if Sanchez has a bad drive, quarter or game, fans will call for Sanchez’ head and the Jets will bring in Tebow. But such analysis never goes beyond that. If the Jets do make Tebow the starting quarterback, and he does well, that’s a good thing. If the Jets bring in Tebow, and he fails, New York can go back to Sanchez. At that point, even if Sanchez has some struggles, the calls for Tebow will be muted. However, some will argue that if Sanchez is benched even once his confidence will be shot.

You may find it absurd to suggest that benching a professional athlete may be enough to derail a great career; in fact, that’s what I originally thought. But after combing through the annals of NFL history, I’m unable to find any proof in the other direction. Truth be told, I do think having two quarterbacks is essentially the football kiss of death. Don’t believe me? Let’s take a stroll down memory lane.

In the early ’50s, the Los Angeles Rams alternated Norm Van Brocklin and Bob Waterfield as their quarterbacks. In 1950, the team averaged 38.8 points per game while each quarterback started six games, and Los Angeles won the championship the next season. But while both Van Brocklin and Waterfield would end up in the Hall of Fame, neither player is well known today by most fans.

A few years later, the Giants would have Don Heinrich as the nominal starter for the first series or two before having Charlie Conerly come in and replace him one the coaching staff had a better read on the opposing defense. Sure the team won the NFL championship in 1956 using this method, but New York ultimately lost the championship to Baltimore in both ’58 and ’59, and neither Heinrich nor Conerly were able to slow down Johnny Unitas in either gmae. In John Eisenberg’s great book on the late ’50s Green Bay Packers, he explained how Vince Lombardi treated Bart Starr like a yo-yo, inserting him and out of the lineup. And while Starr would achieve some success in the ’60s, he ultimately failed as head coach of the Packers in the ’70s and ’80s, going 52-76-3 in 9 uneventful seasons.

Len Dawson failed to impress in Pittsburgh or Cleveland, before giving it one last shot with Lamar Hunt’s AFL franchise in 1962. But the damage had already been done to his pysche, and after going just 1-4 in five starts in 1975, Dawson was forced to retire from the game at the age of 40.

Earl Morrall replaced an injured Unitas and led the Colts to the Super Bowl in 1968, a game Baltimore famously lost. In 1970, Unitas was benched for Morrall in week 2 after playing miserably against the Chiefs. Despite the benching, Unitas would remain the starter for the rest of the year, and the Colts wound up making it to the Super Bowl that season. Trailing 13-6 against the Cowboys, Unitas suffered a rib injury that would have sank most team’s chances. And though Morrall came in and led Baltimore to a come-from-behind victory, it was the worst Super Bowl game ever played. Two years later, Morrall replaced an injured Bob Griese and led Miami to wins in its final 10 games of the regular season. He then helped Miami win its first two playoff games, but Don Shula selected Bob Griese to start Super Bowl VII against the Redskins. While the flip-flop worked in the short term, Miami to this day has never had another undefeated season.

Terry Bradshaw had an uneven first three seasons, prompting Chuck Noll to bench him at the start of the 1974 season. Joe Gilliam led Pittsburgh to a 4-1-1 record, before Noll reinserted Bradshaw as his starter. But the damage was already done: the crippling blow to Bradshaw’s confidence prevented him from failing to win the Super Bowl not only in 1976, but in 1977, too.

In 1987, Joe Gibbs alternated multiple times between Jay Schroeder and Doug Williams. In December, Williams was benched apparently for good, until a few weeks later Schroeder was again benched for Williams. In the playoffs, Doug Williams would start every game, and while he led Washington to a win in Super Bowl XXII, he played miserably in the first quarter. That same season, Steve Young excelled in relief of Joe Montana, and San Francisco entered the ’88 season with a quarterback controversy. Young and Montana both started games in 1988, but their rift would ultimately divide the team. San Francisco was only able to win the Super Bowl that season and the year after, failing in their bid for a three-peat in 1990.

In 1995 and 1996, Pittsburgh would occasionally bring in Kordell Stewart as a third-down/short-yardage/red zone quarterback, and the Steelers struggled to win just 21 games during those two seasons. Minnesota cycled through Brad Johnson, Randall Cunningham, Jeff George and Daunte Culpepper between 1997 and 2000; as a result, the Vikings ranked only 2nd during that time frame in points scored.

Jeff Garcia was an undrafted free agent, and went to Canada for five years. He struggled to a 2-8 record in 1999 with San Francisco, lost his first start in week 1 of the 2000 season, and was benched the following week for Rick Mirer. The benching was the last straw for Garcia. Technically, he wound up making the Pro Bowl that year, the first of four in his career. But while he married a Playboy Playmate, she just turned 30.

In week 8 of the 2000 season, Trent Dilfer came off the bench to replace Tony Banks. While the Ravens would win the Super Bowl, Dilfer is now on ESPN all the time.

Drew Brees tore his labrum and was shown the door by the Chargers after the 2005 season. His confidence shattered, he couldn’t sign anywhere else but in New Orleans. While it worked out okay, we can’t ignore the fact that it took him months and months to get a new contract this off-season.

The 2007 Cleveland Browns staged a quarterback battle between Derek Anderson and Charlie Frye; in the end, Romeo Crennel selected Frye to start week 1. When Frye struggled, Crennel chose to go back to Anderson, but at that point, his sense of self-worth had left the building. While Anderson would make the Pro Bowl and lead the new Browns to their best record since re-entering the league, he was not named a first or second team All-Pro by any major publication. Arizona experienced a multi-year quarterback controversy with Kurt Warner and Matt Leinart, which failed as the Cardinals only made it to one Super Bowl during the Warner/Leinart era, in 2008. That same season, the Titans went from Vince Young back to Kerry Collins, but Tennessee still managed to lose three games.

The Eagles’ succession plan involved going from Donovan McNabb to Kevin Kolb. But in 2010, Michael Vick and Kolb got into a quarterback battle which threatened to tear apart the team. And while Vick would win the job and then the AP Comeback Player of the Year award, he threw a costly interception against the Packers in the playoffs.