The Bears aren't officially doomed—if the playoffs started today, they wouldn't even be the last seed—but things look grim without Jay Cutler and Matt Forte, the latter of whom is has been holed up in Tommie Harris's home hyperbaric chamber. It's going to be several hangover Sundays from here on out.

But if you can overlook or come to terms with the bad news, this Sunday will be fascinating, since the Bears go up against the most interesting storyline in the NFL this year: Tim Tebow.

Even with three of his peers having extraordinary seasons—Aaron Rogers's near-perfection, Drew Brees's staggering yardage, and the pinball numbers Cam Newton is putting up in a one-man show for an awful Panthers team—Tebow is getting most of the attention.

Some of it is for less-than-admirable traffic-bait reasons, as the habitually and publicly devout Christian has been turned into an avatar of the culture war by the Paul Harveys of the sports world, who read into Tebow's welcomed but not atypical magnaminity the stature of a philosopher king:

Consider the interview Tebow gave to the NFL Network's game crew following the Broncos' victory over the New York Jets, a game in which he failed to record a single touchdown pass. When asked how it felt to know that, despite the criticism from myriad corners across the NFL, Broncos fans and his teammates believed him, Tebow responded: "It makes me feel really good. You want people to believe in you; you want people to care about you, and that makes me feel good."

That response is refreshing because it communicates a level of sincerity most professional athletes seem too insecure to display. I've listened to hundreds of interviews with athletes and usually when an interviewer asks an athlete whether he cares about what fans think, that athlete gives a stock response along the lines of "I don't care what fans think."

[snip]

Perhaps it is because Tebow is as physically tough as any quarterback in the game and unafraid to put his shoulder down and challenge All-Pro defensive backs that he doesn't feel the need to fake a level of indifference and hope that it will make him seem more macho than he actually is.

I don't disagree with Tebow's sentiment, but it's also much more common than that writer describes—Jay Cutler has been expressing his gratitude to fans about their support during his injury all week on Twitter, and their relationship to the Bears' QB hasn't quite been the lovefest Tebow's had in Denver.

What's interesting about Tebow is not his status as a semi-voluntary culture warrior. It's that no one knows what to make of him on the field itself. He's a riddle, and riddles are fun. He came out of college as a rare talent, but not the kind that usually translates well to the NFL: good at lots of things, not good enough at any of them to succeed in the highly specialized, scheme-dependent world of the NFL, like so many option quarterbacks who came before him.

Tebow is a bad quarterback, with poor mechanics, a long, awkward delivery, and spotty accuracy. As Dave Zirin memorably describes him:

Tim Tebow throws a football like someone heaving a ham-shaped grenade. It needs to be seen to be believed. I’ve never used this phrase to describe an NFL quarterback, and hope I never have to again, but he’s thrillingly campy.

He's been compared to Michael Vick, but he's not the running threat that Vick is. From what I've seen of Tebow, he's quick and fast, but not really both at the same time: he's quick enough to evade linebackers and fast enough to get out into the open field, but not fast and quick enough to be a breakaway threat (Vick has averaged 7.2 yards per carry on his career; Tebow, 5.6 YPC). The advantage he has over Vick is that he's bigger and taller—he carries a lot of momentum, and will hopefully be less fragile than Vick over the course of his career.

Nonetheless, he's 6-1 this year as a starter. Granted, he's benefitted some from other teams' bad luck: the Jets, who lost their two best running backs, and the Chiefs, who lost their starting quarterback. He's benefitted from other teams' incompetence, like the Vikings' awful secondary, against which he had his best passing game. He's also been the beneficiary of some excellent defensive performances. But he's done just enough to get the Broncos over the top, with three straight wins of four points or less.

Perhaps what makes Tebow good is a keen sense of the limitations he's famous for. Though he throws the ugliest ball in football and has completed less than half his passes, he's thrown just one interception to ten touchdowns. As Bill Barnwell puts it:

Whether it's the location of his incomplete passes, a scheme built to avoid putting him in situations in which his throws are dangerous, some incredible amount of skill, or total blind luck, Tebow's basically the safest quarterback in football when the ball is in the air. He's thrown just four interceptions in 229 attempts during his 10 starts, producing a ridiculous interception rate of 1.7 percent. This year, he's gotten even stingier, with just one pick all year and an otherworldly interception rate of 0.6 percent.

I suspect the scheme has a lot to do with it—the spread option opens up the field, giving the Broncos two running threats and several passing threats (his receivers also seem to have a knack for bailing him out of underthrown passes). But judgement also appears to have a lot to do with it. Being unable to thread the ball through the defense, he doesn't; he checks down, dumps off, settles for short passes, or runs. Meanwhile, the Broncos lay back and wait for their more skilled but more conventionally defended opponents to screw up, a pick-six being as good as a Tebow touchdown.

Cold Hard Football Facts has something called a "Real QB Rating," which aims to measure "all aspects of quarterback play, passing, rushing, sacks, fumbles, etc." It's a good demonstration of how Tebow makes up for his low yards per completion and even worse accuracy, the lowest of any starting quarterback in the NFL (only two are below 50 percent, Tebow and Blaine Gabbert), by protecting the football, avoiding huge losses on sacks, and running.

Tebow comes into this week as a mystery, which neither the nerds nor the pros can figure out: in a hilarious NFL Network roundtable, Vikings great Darren Sharper seems almost offended that his old team got shredded by such an incompetent passer. It's instructive to watch four retired players, representing four different positions—Sharper, Michael Irvin, Marshall Faulk, and Warren Sapp—try to wrap their brains around what they see versus his results. They don't know. Bill Barnwell doesn't know: "We see very little statistical evidence to suggest that Tebow has a viable career as a pro quarterback ahead of him. On the other hand, if anyone is going to be an exception to quarterback statistics, it's going to be Tebow."

Mysteries require good tests, and the Bears will be an excellent one. As another NFL Network roundtable pointed out, the Bears have shut down Michael Vick, thanks in part to the man they call "Vick Kryptonite," Julius Peppers. The Bears gave up 29 points against Cam Newton and the Panthers, not something they can do against a good Broncos defense with Caleb Hanie at the helm and Kahlil Bell behind him. But Newton is a much, much better passer than Tebow, putting up 374 yards against the Bears' defense. Newton only managed eight carries for 35 yards, a modest 4.4 yards per carry. Vick ran five times for 34 yards in Week 9.

Sunday will be a test for the injury-riddled, ill-fated Bears. But it's an even bigger test for Tebow: though he'll play teams that are better overall, he won't face a defense that's as well-designed to shut him down. With two deeply flawed young quarterbacks facing good defenses, it will be an ugly game, but in some ways it should be one of the most interesting you'll see all year.

Related: Dan Pompei on the Bears' Bobby Douglass, a Tebow prototype from the 1960s and 1970s. He does look awfully familiar.

Photograph: Jeff Kearn (CC by 2.0)