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The Jets are stuck with Mark Sanchez as the starting QB, likely through the end of the 2013 season, due to the terms of his contract and the dearth of better options on the roster. For better or worse, Sanchez will likely be the Jets starting QB for at least another year and change. Given that set of circumstances, the question arises, what can we expect from Sanchez next year? As a thought experiment, let's assume the best for 2013's supporting cast, as follows. Let's assume for the purpose of argument Holmes is back and healthy, Kerley continues to develop, Hill learns to catch and becomes a positive force, the coaching staff finds a way to keep Keller and actually utilize McKnight, and one high drat pick is used on a RB or WR. All of that is pure conjecture, and best case scenario kind of stuff, but what if that is how it plays out? At that point the Jets go from having one of the worst set of skill position weapons in the entire NFL to having an above average surrounding cast. In a really Pollyana scenario, Hill rapidly develops and becomes the elite WR his physical talents say he should be. I know, this is all very unlikely, but let's just play the what if game for the time being. What then?
In evaluating Mark Sanchez's play this year, some have pointed out the dearth of surrounding talent at the skill positions as a reason Sanchez has struggled. Others have argued that great QBs make the surrounding talent better, and a QB like Peyton Manning or Tom Brady have thrived with lesser talent surrounding them. Both arguments are true, as far as they go. The interesting question to me is, how much does surrounding talent affect QB performance? Can it be quantified in any reasonable way, and if so, what might the performance of Mark Sanchez look like if he was surrounded by better talent? This is a very difficult question to answer in a vacuum. Fortunately for us, real life has provided an almost perfect example of a QB career split in nearly equal halves, one half with mediocre to bad surrounding skill players, and one half with excellent surrounding skill players. That career is the career of Tom Brady, and what his numbers show go a good way toward solving the puzzle of how much surrounding talent matters.
Tom Brady's career can be split neatly into the years prior to 2007 and the years from 2007 on. Prior to 2007 Brady, for most of that period, had talent at the skill positions similar in many respects to Sanchez's current surrounding cast. Below average talent at WR, RB and TE. Brady and the Pats won 3 SBs with a dominant defense, a clutch QB, and below average offensive talent. Brady's numbers for those years were good, but hardly HOF worthy. Brady was remarkably consistent for this 6 year stretch. He had a QBR that averaged 89, never coming in below 86 or above 93. For 5 of those 6 years he never had more than 28 nor less than 23 TD passes, averaging 25 for the period. For 5 of those 6 years he never was sacked more than 32 nor less than 26 times. For 5 of the 6 years he never averaged more than 7.8 nor less than 6.8 yards per attempt, averaging 7.1 for the period. During that period he never completed less than 60% nor more than 64 % of his passes, averaging 61% for the period. In short, he was a model of consistency, and he was consistently good, but not off the charts great.
Then came 2007. Belichick, recognizing that the defense that had carried him to 3 SB titles in 4 years was crumbling with age and not being replaced with good new talent, made a fateful decision. He decided to go all in on Tom Brady, surrounding him with a whole new cast of receivers, led by All Pro WRs Randy Moss and Wes Welker. From this point on, the Pats made a conscious decision to ride their greatest talent, Brady, and surround him with the best skill players they could acquire. This has been the Pats game plan ever since. It hasn't gotten them any new SB titles, but it has gotten them something of a brand new QB, a QB who has ever since performed at an All World level. In the slightly more than 4 1/2 seasons since the huge upgrade in surrounding talent, Brady has been transformed. Whereas before 2007 he never had a QBR higher than 93, since 2007 he has never had a QBR lower than 96. Before 2007 he never passed for more than 28 TDs - since 2007 he has never had a year with less than 28 TDs. Before 2007 he never completed more than 64 % of his passes; since 2007 he has never completed less than 65 % of his passes. The overall numbers, from 2007 on, read like this: QBR 107, yards per attempt 8.1, TDs 38, Completion % 66.3.
So here we have an almost perfect experiment in the value of surrounding talent. For Tom Brady, the upgrades around him meant tacking on 13 TD passes, 1 yard per attempt, +5% to his completion percentage, and plus 18 points on his QBR. It meant the difference between a good QB known more for his clutch play than his elite #s and an elite QB racking up HOF #s that now have him being mentioned in the conversation for the GOAT. In short, it meant a hell of a lot.
Now, completing the thought experiment, let's assume that Sanchez's upgrade at the skill positions will not be nearly so drastic as Brady's was. For the purposes of discussion, and just throwing a number out there, let's say Sanchez's upgrades amount to only 60% of what Brady's were. What then might we expect from Sanchez next year? If we apply the Brady upgrade numbers and multiply by our arbitrary 60% Sanchez factor, then we can expect Sanchez to improve by 8 TD passes, 0.6 yards per attempt, +3% to his completion %, and plus 11 points on his QBR. That amounts to maybe 25 TDs, 7.3 yards per attempt, 59% completion %, and an 87 QBR. Those numbers would make him almost exactly a league average QB.
Now, of course there are a ton of somewhat arbitrary assumptions in this analysis. Things never play out so neatly, and the projected numbers presented here are to be taken with a very large grain of salt. Nonetheless, the core of the argument presented stands, I think, on fairly solid ground. Supporting casts do matter, a great deal in fact, and Brady's career is a nearly perfect example that helps us to roughly quantify just how much they matter. Given what we discussed here, it is not a ridiculous stretch to muse that what we have in Mark Sanchez just might be a decent, roughly league average QB, hidden by an abysmal supporting cast. That's still not great, it's still not anything close to elite, but maybe, just maybe a 2013 with Sanchez behind center is not going to be the complete train wreck we all envision.