Oregon's defense is better than it's getting credit for. But it's different. It's not trying to beat the opposing offense with skill. And, for the moment at least, it's going to work better than I've seen any analyst give it credit for.
So, what is it Oregon's defense does? I've seen a few people make comments indicating they get it, but I haven't seen anyone explain it yet. The closest I've seen is a remark comparing Oregon's defense to hockey, with their frequent line changes. So here's my attempt.
To figure out what's going on, look at the obvious stuff. 25 different players (give or take, depending on injuries) play downs on defense every game. The defense starts out barely able to stop anything, and eventually reaches a point where it's strangling the opposing offense, usually in the second half. But it's not generally strangling them with three-and-outs. It's killing them in the red zone, as they turn the ball over due to sloppiness, or turning over on downs as they go for it on 4th out of desperation.
So what conclusion do I draw from this? I conclude that the defense plays to exhaust the opposing offense, then take advantage of their mistakes as fatigue takes over. They play to physically punish the offense on every play. Make them work, hard, to get their yards. It's ok to give up yards. It's ok to give up points, even. The key is to force the offense to struggle for them. Make the offense get tired. Make the offense run out of gas by the second half, with a combination of physical play, conditioning, and heavy rotation at every position on defense.
So, let's look at the tradeoffs this defensive strategy makes:
First, it needs to be paired with a brutal offense. If the offense can't provide pressure to score on the opposing offense, they're free to play conservatively, punting often, and conserving energy. Or even worse, the points they score early might be enough to win, flat-out. This defense can't work if the offense isn't threatening to race the other team.
Second, it requires greater depth and conditioning than the opposing offense. If the defense tires before the opposing offense, this strategy backfires in a very ugly way.
But third, and most important - opposing offensive skill is nearly irrelevant. This defense doesn't attack skill. It attacks conditioning and depth. Sure, put together your unstoppable 5-minute drive consisting of 16 plays. Do it again a few minutes later. Maybe even a third or fourth time. But you're getting physically punished every time. Can you do it one more time, to take the lead again, after you're already exhausted? Or are you going to start making mistakes, and turning the ball over? The only time opposing skill matters is if the defense is so out-classed that they can't make the opposing offense pay for their yards. But that situation doesn't seem likely to come up often in CFB-land.
So, at the moment, the situation is perfect for this defensive strategy. Oregon's offense is more explosive than anyone else's. The defense has enough raw skill to make opposing offenses pay for their yards and points, and the offense provides constant pressure to score on the opposing offense. And Oregon's team conditioning and depth is far better than anyone else they've played. That's going to continue through the rest of the season. There's a good chance it will even hold in whatever bowl game they end up in.
But if Oregon sustains success over a couple more years with this strategy, the lay of the land is going to be changed by it. Other teams are going to start conditioning as hard as Oregon, and developing depth of their own. If Oregon sustains success like this, I can't predict what will develop because of it.
But for now, the defense is better than most analysts recognize, because their goal is different than anyone else's. And this year, the team is built to make the most of it.