That's right. Four weeks into the season, and it's officially a replay of 2009, with the SEC and Pac-10 dominating the top of the poll. Alabama, with a perfect record against an 8-8 schedule -- one of only 15 teams in the top 45 with a schedule at or above .500 -- as well as the poll's top scoring defense and one of the few quality wins available (as you will see, the best win of the season, at least in the poll's eyes), ascends to the top spot. They're followed closely by Florida, who hasn't looked particularly impressive on the field but nevertheless has a +94 margin against a 9-6 schedule.
At this point in the season, there is little separating the top 5. Stanford drops out of the top spot but gets by on pure performance, with a combined schedule record of 7-9 (including two road wins) and an FCS victory but a ridiculous margin of +137. Arizona and LSU are SOS superstars, with undefeated records against two of the top three schedules in the poll; their opponents are a combined 20-3 in games not against them.
At this point in the year, with four weeks of schedule data creating big strength of schedule scores -- both positive and negative -- SOS is at its most powerful, and can trump the fact that a team with a weak schedule ran through them like a Tiger tank. Take Oregon, former BlogpLOL #1, which continues to fade as more strength of schedule information becomes available. The Ducks -- the only team to score 200 points through week 4 and a runaway leader in margin of victory with +187 --have played an atrocious 5-13 schedule, including a win over a 1-2 FCS opponent and the worst I-A team I've ever seen. It's hard to move UO ahead of Mizzou (+95 MOV against 8-6 schedule, including 2-1 Illinois and 3-1 SDSU) or TCU (+116 MOV agaisnt 7-8 schedule, including a road win and a neutral-site win). Oregon is starting to look like last year's Cincinnati squad, which pummeled middling opposition all year but still couldn't hide the fact that the opposition was middling.
Another team getting crucified by schedule weakness is the Nebraska Cornhuskers, who (it's not a typo) fell to #22 based on a +109 MOV against an atrocious 3-11 schedule; the best team Nebraska has faced so far might well be Idaho. The poll formula expects an end-of-season .500 team to be 4-0 against that schedule with a +101 margin, so the Huskers' performance to date isn't exactly setting the world on fire. Again, it seems absurd until you look at the teams above them. Northwestern has two road wins against a far better schedule, Florida State has better numbers across the board (if you're willing to look past that pesky loss to Oklahoma), and Utah has done better (+126 MOV) against a similarly bad 3-12 schedule.
On the other side of the ledger, Penn State shoots up the poll on the back of the best schedule in the country to date. The Nittany Lions' opposition is an astonishing 10-1 against other opponents; even their I-AA cupcake has steamrolled its other opposition. The Lions' schedule will only improve in the next two weeks, with games against Iowa and Illinois. The other big upticks in this week's poll -- Auburn, Michigan, and USC -- did it the old fashioned way, by playing the occasional road game, avoiding I-AA opponents (except for UM), and getting lucky with non-conference opponents who aren't terrible.
Fortunately, unlike last year, we don't have to wait for the SEC Championship Game to settle the debate at the top. Alabama plays Florida this week. Stanford plays Oregon. Barring a blowout by Arizona or LSU, the winners of those two games should jump to the top for week five. Aside from the top tier, the rest of the poll is slowly rounding into shape. Expect more volatility next week, based solely on the number of games between ranked teams, but eventually the waters will calm.