Why, I wondered? Joe Flacco has been durable as a starter, not missing a game in two seasons. Coach John Harbaugh had Troy Smith and John Beck as young backups, even though they have only one NFL regular-season win between them. In fact, Beck, drafted by current Ravens offensive coordinator Cam Cameron when he was the coach of the Dolphins, still has the potential to develop into a starter somewhere in this league.
Bulger would be the perfect fill-in if Flacco suffers an injury. But the Bulger signing also firmed up how little faith the Ravens have in Smith and Beck and how bad the backup quarterback position is in the NFL. Thanks to the development of young quarterback studs such as Flacco, Matt Ryan, Ben Roethlisberger, Eli Manning, Philip Rivers and others, the starting quarterback position is as deep for quality as it's ever been in the NFL.
On the flipside, the backup landscape is a desert. More good teams have unknown, unproven quarterbacks behind the starter than ever before. An injury to a starting quarterback could take a 13-win team to six or seven wins in an instant.
Sure, the Patriots came off an undefeated regular season in 2007 and won 11 games with Matt Cassel, who hadn't started since high school. What's forgotten is that Patriots team was loaded. Cassel threw to a great set of run-after-the-catch receivers. The defense was solid. The offensive line was in its prime. And don't forget, all four AFC East teams were playing one of the easiest schedule combinations in the past five years; they played the AFC West and NFC West when both divisions were down.
Football people talk about the value of a backup quarterback, but so much of it is just talk. Behind Brady in New England is Brian Hoyer, an undrafted rookie from 2009 with zero starts. Behind Peyton Manning are Curtis Painter and Tom Brandstater. Chad Henne is backed up by Pat White in Miami because Chad Pennington is coming off shoulder surgery and is a question mark for the start of the season. Former Chief Tyler Thigpen is also in the Dolphins' mix. Jim Sorgi, who has no starts, moved from Indianapolis to the Giants to be Eli Manning's backup.
If anything happens to Jay Cutler in Chicago, Lovie Smith's job security is in the hands of unproven Caleb Hanie, an undrafted quarterback from 2008. The Packers have been grooming Matt Flynn behind Aaron Rodgers the past few years, but like all Packers backups since Brett Favre, none get regular-season playing time.
Before the start of training camp, the Jets and Saints are expected to make veteran backup moves. Mark Brunell may be heading to the Jets and the Saints are expected to sign Patrick Ramsey. Because both teams were in championship games last season, they were limited in the number of unrestricted free agents they could sign. That rule ends when training camp starts, so the door is open for them to bring in Brunell, Ramsey or anyone.
Still, that's pressing it. Coaches talk about the need for all players to be in offseason programs and OTAs to learn the system and practice with the team. Brunell and Ramsey will be coming in at the last minute and picking up the offense on the fly. While the Jets can fall back and rely on Kellen Clemens as a backup, the Saints have gone the entire offseason with Chase Daniel as the backup.
All of this cries for the NFL to firmly establish a developmental league for players, particularly quarterbacks. The state of backup quarterbacks in this league is abysmal.
Part of the problem is one of the league's successes. Because officials are quick to penalize late hits or low hits on quarterbacks, more starters are lasting longer into the season. That's great for the game because the league has evolved into a passing sport with more throwers adept at making great fourth-quarter comebacks.
Under normal circumstances, an offense figures to lose five or six points per game if it goes to a backup. You know the theory of longtime NFL coach and current Colts radio analyst Ted Marchibroda? He says a good backup quarterback can win you three games, but if you play him six games, he'll lose you three.
In other words, a good backup can keep a good team around .500 the longer he plays. A bad backup, though, can get a good team into the top 10 of the next year's draft if he plays too much.
Even the teams that have experienced backups may not have the right fits. The Eagles are standing by Michael Vick despite a recent shooting at his birthday party because they believe his story. But is he really a good backup? Vick has the mind of the starter, and he's only a backup because teams aren't stepping up to acquire him as a starter.
Can displaced starters such as Derek Anderson (Arizona), Rex Grossman (Washington), Brady Quinn (Denver), David Carr (San Francisco) and others step up as injury replacements and not cause significant drop-offs?
More credit should be given to the teams, such as Dallas (Jon Kitna), Baltimore (Bulger), Pittsburgh (Byron Leftwich and Charlie Batch) and Tennessee (Kerry Collins), that realize a franchise is only one hit away from disaster at quarterback. Two years ago, the Titans lost Vince Young during the first week of the season. Collins came off the bench in what turned out to be a 13-win season.
The league suffers when a talented thrower such as JaMarcus Russell washes out his career at age 24. It needs a developmental program. J.P. Losman benefited from the coaching and playing he had in the UFL's first season, parlaying it into a free-agency pickup by the Seahawks.
Along with getting a collective bargaining agreement, the NFL needs to either work out a deal with the UFL as its developmental league or create its own to develop more quarterbacks. The urgency is apparent if you study quarterback depth charts.
John Clayton, a recipient of the Pro Football Hall of Fame's McCann Award for distinguished reporting, is a senior writer for ESPN.com.