For this study, I looked at all 61 quarterbacks drafted in the first round between 1983 (the greatest quarterback draft ever and the one that featured three of the first truly modern quarterbacks of our era in Marino, Elway, and Kelly) and the present. I threw out every player who hadn't been in the league for three years, since, fair or not, that seems to be the evaluation period given to everyone in the NFL, which dropped the number down to 54. Of those 54, I came up with 23 that I considered "Busts", 18 "Average" QBs, and 13 "Franchise" QBs.
Out of those 54 quarterbacks, 13 didn't start a single game their rookie year. Four of those quarterbacks became Franchise players (Aaron Rodgers, Philip Rivers, Carson Palmer, Jim Kelly (for fairness sake, it should be noted that Kelly spent two seasons playing for the USFL's Houston Gamblers), five became average, serviceable starters (Jason Campbell, Chad Pennington, Daunte Culpepper, Jim Harbaugh, and Ken O'Brien), while four went bust (Brady Quinn, JP Losman, Kelly Stouffer, and Todd Blackledge). Obviously the results of this group show that sitting the bench for one's rookie year has no quantifiable effect on future performance, as the distribution is almost identical for each group (4 franchise, 5 average, 4 busts.)
The biggest, and least successful group, were the 20 quarterbacks who started 1-5 games their rookie year. Only one Franchise quarterback is in this group (Steve McNair), while there are a whopping 11 busts (JaMarcus Russell, Patrick Ramsey, Akili Smith, Jim Druckenmiller, Trent Dilfer, Tommy Maddox, David Klingler, Todd Marinovich, Dan McGwire, Andre Ware, and Chuck Long), and 8 average QBs (Rex Grossman, Michael Vick, Vinny Testaverde, Chris Miller, Jim Everett, Tony Eason). My logic as to why this group is so unsuccessful? Looking at those busts, almost all (outside of JaMarcus), were guys with overrated skills that would probably not be first round picks today.Ware and Klingler were average guys who had inflated numbers in a Run N' Shoot offense, Long was simply a guy who started a lot of games at Iowa and thus set a bunch of records, while the others all were lacking in talent as well. The most logical explanation for why those busts failed to start more than 5 games is simply that they weren't talented enough to be the best quarterbacks on the roster, which doesn't appear to be the case for Sam Bradford.
The 6-10 games started group is mostly hit or miss: John Elway, Dan Marino, Eli Manning, and Donovan McNabb were/are all franchise players, while Kyle Boller, Ryan Leaf, Heath Shuler, and Cade McNown went bust, and only Alex Smith appears to be blossoming into an average quarterback.
The 11-15 games group has only a few names at the extremities (Aikman and Roethlisberger are franchise guys, Joey Harrington and Matt Leinart are busts), but plenty of average players (Tim Couch, Byron Leftwich, Kerry Collins, Vince Young, Jeff George, and Drew Bledsoe).
Only five rookies have started all 16 games in that time period, two of which don't make this list yet (although if I had to guess, both Joe Flacco and Matt Ryan will be in the Franchise category). Of the three who do, the results are complete polar opposites, with Peyton Manning representing the Franchise QBs and David Carr and Rick Mirer hanging out with the busts.
So what does all this mean for Sam Bradford? Does it really not matter at all how many games he starts? I'm submitting that (outside of the injury risk, which is huge no matter when you play), it really doesn't matter whether he starts or sits. What matters more is the team's approach to him in the future, meaning how do they build their team to help Sam Bradford?
Let's look at the Busts and Franchise QBs on this list and determine why they succeeded or failed, outside of the # of games they started as rookies:
Busts-
JaMarcus Russell, Brady Quinn, Matt Leinart, JP Losman, Kyle Boller, David Carr, Joey Harrington, Patrick Ramsey, Akili Smith, Cade McNown, Ryan Leaf, Jim Druckenmiller, Trent Dilfer, Heath Shuler, Rick Mirer, Tommy Maddox, David Klingler, Todd Marinovich, Dan McGwire, Andre Ware, Kelly Stouffer, Chuck Long, and Todd Blackledge.
Now, first of all, in many of these cases, as I mentioned above, the scouting system simply failed and these guys were unsuccessful because they lacked the talent (McNown, Shuler, Maddox, Klingler, McGwire, Ware, Stouffer, Long).
Another group consists of guys who had NFL caliber arms but had accuracy issues and decision-making problems that were destined to preclude them from being consistent NFL starters (Losman, Boller, Ramsey, Akili Smith, Druckenmiller, Dilfer, Blackledge)
All of those guys above were simply just poor draft decisions by the team that took them. The last group (Russell, Quinn, Leinart, Carr, Harrington, Leaf, Mirer, and Marinovich) all failed for a number of reasons. JaMarcus Russell has been dissected a lot since his release, and there are two main reasons for his failure: poor work ethic and a dysfunctional organization. Brady Quinn and Matt Leinart both struggled by being blocked by two guys that weren't Supposed to block them (Derek Anderson and Kurt Warner) and have had to endure changes in the coaching staff and a lack of support from the new regimes. Ryan Leaf , Rick Mirer, and Todd Marinovich all failed for mostly personal reasons (Leaf's immaturity, Mirer's stupidity, and Marinovich's drug habits).
Harrington and Carr, however, arguably failed because of terrible supporting casts. Carr had a god awful offensive line that allowed him to get sacked 72 times as a rookie and 249 times total (an average of almost 3 1/2 sacks per game) during his time with the Texans, and was never the same afterwards. Harrington had a good offensive line, but mediocre talent at runningback (James Stewart, Kevin Jones), notoriously terrible draft picks at wide receiver (Charles Rogers, Roy Williams, Mike Williams), and a truly dysfunctional organization that had no idea how to handle a young quarterback. No one can ever truly absolve Harrington or Carr of All of the blame, I suppose, but they were placed in extremely difficult situations.
Harrington and Carr, however, arguably failed because of terrible supporting casts. Carr had a god awful offensive line that allowed him to get sacked 72 times as a rookie and 249 times total (an average of almost 3 1/2 sacks per game) during his time with the Texans, and was never the same afterwards. Harrington had a good offensive line, but mediocre talent at runningback (James Stewart, Kevin Jones), notoriously terrible draft picks at wide receiver (Charles Rogers, Roy Williams, Mike Williams), and a truly dysfunctional organization that had no idea how to handle a young quarterback. No one can ever truly absolve Harrington or Carr of All of the blame, I suppose, but they were placed in extremely difficult situations.
Now, looking at the 13 franchise quarterbacks-
Jay Cutler, Aaron Rodgers, Ben Roethlisberger, Eli Manning, Phillip Rivers, Carson Palmer, Donovan McNabb, Peyton Manning, Steve McNair, Troy Aikman, John Elway, Dan Marino, and Jim Kelly
-One theme is fairly common here. Almost all of them played for good teams when they were rookies. Rivers, Palmer, Rodgers, and Kelly didn't play their rookie years, but the Chargers were a winning team the two seasons in which Rivers sat the bench and had an extremely talented core around him when he finally did take over in 2006 and went 14-2. Carson Palmer's Bengals were 8-8 in his rookie year and his first year as a starter in 2004, and featured a talented group of wide receivers with Chad Ochocinco (nee Johnson) and TJ Houshmanzadeh, as well as a strong running game with Rudi Johnson. Rodgers sat beyond Brett Favre, and while he went 6-10 as a starter his rookie year, he inherited a team that went 13-3 the year before (and 11-5 the year after) and had an extremely talented offensive unit, with wideouts like Greg Jennings and Donald Driver and a strong running game behind Ryan Grant. As I mentioned, Jim Kelly played for the Houston Gamblers of the USFL, and by the time he came to the Bills in 1986 they had the brilliant Marv Leavy at head coach and already had wide receiver Andre Reed. Despite going 4-12 in Kelly's "rookie year", the organization was clearly on it's way up.
Of the quarterbacks who did start games their rookie year, 4 of the 9 (Jay Cutler, Ben Roethlisberger, Dan Marino, John Elway) played for team's with winning records that had talented offensive players around them.
Of the 5 quarterbacks who started for losing teams their rookie years (Eli Manning, Donovan McNabb, Peyton Manning, Troy Aikman, Steve McNair), 4 of the 5 had non-losing records the next year, while 3 of them (the Mannings and McNabb) took teams to the playoffs in their second year, meaning they had teams that rebuilt quickly in other areas as well (the Giants adding Plaxico Burris on offensive to help Eli, the Colts drafting Edgerrin James). McNair's Titans built up a strong offensive line and drafted Eddie George to help in the run game, while Aikman's Cowboys added Emmitt Smith the year after Aikman (as well as Michael Irvin the year Before Aikman) to create the famous "triplets."
So what's the secret to sucess for Sam Bradford? Play for a winning team. Since that looks unlikely, hope to God that the Rams recognize that the most important thing for Bradford's development is to spend high picks the next few years on getting him offensive talent. Steven Jackson should help, but I'm not sure the Rams have the wide receivers or tight ends needed to make plays for Sam, and I'm definitely sure their offensive line is atrocious.
In conclusion, history tells us little as to whether it's better or not for Bradford to start. What it does tell us is that, assuming that he has the talent to be an NFL quarterback to begin with (and I think he does), his team's approach to the 2nd and 3rd years of his career will be far more important. Do they keep the same coaching staff and ensure stability? Do they draft players at their areas of need on offense? Far too many times there are teams like the Lions with Harrington and the Texans with Carr who just assume that quarterbacks will just keep "progressing" until they transform into Pro Bowl quarterbacks. It doesn't work that way. Yes, players should improve each year (Harrington and Carr both did, actually), but they can't take that proverbial "next step" without NFL-quality talent around them. Bradford won't be able to, either.