The SEC only has two undefeated teams left. Alabama being one of them is no surprise. That Missouri is the other seems to be catching a lot of people off guard, but it shouldn't.
The fact that MU is the only conference team besides the Tide with a blemish-free record is a reflection of two larger points. One is that the SEC has spread some of its bigger games towards the front half of the schedule. Of the five losses among the three favorites in each division—Georgia, South Carolina, and Florida in the East, and Alabama, LSU, and Texas A&M in the West—three of them come from within that group. The other two come courtesy of Florida, which derped away its game at Miami (FL), and Georgia, which lost to a top-five Clemson outfit. Bama is the only one of the six to come this far with a zero in the loss column, but only the Gators have something to feel bad about there among the rest.
If you're surprised that Missouri is still undefeated, I can only conclude one or both of two things. Firstly, you probably didn't look at the Tigers' schedule. The first four games on it were non-conference games with the toughest game being a trip to Indiana. The Hoosiers are maybe a marginal bowl team with a loss to Navy. The road hasn't been terribly bumpy.
The other conclusion is that you thought that Vanderbilt would beat Mizzou. It's hard to fault folks too much for that; Vandy won in Columbia last year, after all. However, you probably shouldn't have been thinking that by the time last weekend rolled around. The injury bug bit the Tigers terribly last year, but it hasn't this year. Meanwhile, Vandy is on a scheduled down year. Again, picking VU to win that one wasn't insane, but it became less and less of a good pick as we got closer to it.
Long story short, it couldn't have been that hard to pick the Tigers to go 5-0 because I did it. Now comes the hard part: a brutal stretch of going to Georgia and hosting Florida and South Carolina in consecutive weeks with no bye.
Despite playing no one all that good in the first four weeks, Missouri's defensive S&P+ rated just 42nd in that span (the figures haven't been updated to include the 10/5 games at time of posting). In comparison, Georgia's much maligned defense rates 26th in these opponent-adjusted ratings. The sample size is still too small to make firm judgments, but it doesn't appear that the defense is as efficient as the 28th-rated Mizzou offense is.
And that's the thing of it. Missouri is behind those three upcoming opponents in both offensive and defensive S&P+, save its offense being ahead of Florida's offense. Even so, its defense is miles behind Florida's defense. Missouri is a solidly good team, but it probably should end up no better than fourth in the division depending on variables like how many more injuries Georgia sustains.
Is following a course for fourth in the East really uncharted waters for Missouri? The Tigers were one of the better Big 12 programs over their last half decade in that conference. There was no reason to think that last year's bad injury luck and stiff schedule set a reasonable baseline at five wins.
A lot of folks down this way were really down on Mizzou after 2012 because of the narrative that arose during expansion. Missouri isn't a "real" SEC school. If they can't win the Big 12, they won't win the SEC. They don't know what they've gotten themselves into. They're in over their heads. Then, after last season, people added the idea that Gary Pinkel was close to being fired.
Welcome back to reality. Missouri isn't a bad program. Pinkel isn't a bad coach. It won't take MU as long to reach Atlanta as it took South Carolina to do so, and it'll get there long before at least a half dozen SEC schools go there next.
The Tigers were largely ignored in the offseason, and you can see it in how many people didn't know the schedule and are acting like 5-0 is some big shock. It's not. I am not putting the Tigers in the top tier of the East on a track for the SEC Championship Game just yet, but it wouldn't surprise me if they simply outscored Georgia this weekend (particularly if Todd Gurley can't go).
If Missouri is a surprise team so far in 2013, it's the least surprising one ever.