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“Worldly wisdom teaches that it is better for the reputation to fail conventionally than to succeed unconventionally.” – John M. Keynes.

Photo via phillymag.com.

Last Thursday night, Chip Kelly was widely criticized for an unconventional decision that turned out to be unsuccessful. Trailing 10-0 in the first quarter against the Chiefs, Michael Vick threw a 22-yard touchdown pass to Jason Avant. The photo above shows how the Eagles lined up for the point after. Philadelphia’s two-point conversion attempt — a play known as the the Swinging Gate — was stopped, and it was stopped in particularly ugly fashion. That made it easy to point a finger and laugh at the college coach doing something silly.

But without the benefit of hindsight, there was nothing silly or even suboptimal about the decision. Putting aside the specifics of the play — we’ll get to that at the end — the main criticism seems to be that it was “too early” to go for two, or that the Eagles were “chasing points”, or that it was simply “unnecessary.” All of those are buzz words for saying that the Eagles should have behaved conventionally.

At a baseline level, let’s recognize that a team has a roughly 50/50 chance of converting on a two-point conversion. For a good offense with a mobile quarterback, that number may be even higher, but let’s just use the 50/50 number now. If that’s the case, then teams early in the game should be indifferent between kicking the extra point and going for two. Consider this hypothetical example: if a team had the option of kicking the extra point or flipping a coin — and heads gave them two points, tail giving them zero — would choosing to flip the coin be a poor decision?

Late in games, perhaps. But early in the game? I don’t see any reason to think that the difference between having six versus seven points on the board in the first quarter is more significant than the difference between having seven or eight points. Suppose you were told that your favorite team would score first quarter touchdowns in back-to-back games. Option 1 provides that your team would the extra point both times, while Option 2 is that your team would make the two point conversion once and fail on the attempt once. So you get eight points in one game and six points in the other.

Which would you prefer, Option 1 or Option 2? And why? And, if you prefer Option 1 to Option 2, how much more preferable is it? What would you be willing to trade to land in Option 1 — how many yards on the ensuring kickoff?

I would be indifferent between Options 1 and 2, but even if you preferred one, I don’t see how anyone could strongly prefer Option 1 to Option 2. The value to having 8 points is real, which is why it is never “too early” or “unnecessary” to go for two in a world where teams convert on two-point attempts half the time. Those are red herrings, because going for two is only a high-variance strategy; is it not a high-variance, lower-expected value option. Once you understand that, then nearly all the criticism about Kelly’s decision disappears.

As for the actual play call? I think it was a good one. Keep in mind that the Eagles did not pigeon hole themselves into going for two — based on how the Chiefs reacted to that formation prior to the snap, Philadelphia could have switched back to a normal extra point formation or simply taken a delay of game penalty with minimal harm. But Kansas City did not react well to the play pre-snap: The Eagles split two players out wide to the right, and Kansas City countered with two defenders to that side. But in the middle of the field, Philadelphia had the snapper, holder, and kicker, while the Chiefs kept four players in the middle of the field. I’m quite certain the special teams coach was not pleased with how the Chiefs responded to the situation, because that left K.C. with only five defenders to the defense’s right, while the Eagles were able to match up five blockers to that side and Zach Ertz, the eventual ballcarrier.

That’s a matchup Philadelphia should win more often than fifty percent of the time, and perhaps significantly more often than that. As it turns out, Lane Johnson blew the block, Tamba Hali made a nice play, and Kelly and the Eagles had egg on their face. Failing unconventionally has its drawbacks.

  • http://www.mattwaldmanrsp.com Matt Waldman


  • Anon

    Let’s say the opponent always scores a TD after you do. So in the kicks the XP scenario the opponent always does the same so you’re always tied. In the go for 2 scenario, half the time you fail and the other team kicks the XP and you trail by 1. Half the time you make it and then the opponent attempts a 2P as well, getting it half the time. So a quarter of the time you are up 2 and a quarter of the time you are tied. So is being up 2 twice as good as being up 1? Obviously a simplified example, haven’t really thought it through. Thoughts? Does this “acting first” effect matter early in the game?

  • anon-respond


    There is very little marginal value to being up 2 points instead of 1. This becomes more true the closer you get to the end of the game when the amount of scoring opportunities are limited. (At time=60-:00 being up 0 points is worth 50% payout, and being up 1 or 2 points are both worth 100% of a win). Your guaranteed retaliatory touchdown scenario probably best applies in such an endgame scenario where there is ~2:00 or less on the clock (so your offense won’t be likely to score again) and you are facing an opponent with a strong offense and a conservative conversion decision matrix. In this case it is indeed terrible to be the first actor since the opponent can make perfect decisions after seeing the result of your conversion.

    This line of thought is much less useful the closer we are to t=0 in the game because there are going to be many more scoring opportunities for each team. Our hero team isn’t in such a bad spot being down by one since they can always opt to go for 2 on their next TD, and their next one and their next one… Clearly missing your first conversion attempt puts you at a disadvantage, but not a very large one, since even missing 3 conversion attempts in a row against a team steadily nailing extra points can be tied with a FG.

    Finally, my intuition says that the marginal value of being up 1 vs 2 points matters more at the start of the game. When you are up 2 from a successful hero conversion+ failed villain conversion you are now in a position to simply kick extra points after TDs giving you a lead of 9 and forcing the villain team to score on two possessions to get even or ahead. This should mostly offset the twice-as-often downside of trailing by one since half the time a TD+conversion re-ties the game, and the other half hero is in the reverse 2-possession scenario.

    I’m falling asleep as I write this so apologies in advance for syntax/spelling/grammar/logical failings/faulty assumptions.

  • MaxStout

    I think much of the criticism isn’t about going for two it’s about the “particularly ugly fashion” of the failure. There’s a story on philly.com where you can view all of Oregon’s two point tries over the pact couple of years. philly.com/philly/blogs/red_zone/Chip-Kelly-2-point-conversion-GIFs.html They were successful on 13 of 16 attempts, almost all out of the swinging gate. There are several variations from the formation. The play that the Eagles tried was the same play that was successful for Oregon in the Tostitos Bowl, K State had lined up 6 players to the right so they had a man unblocked but still wasn’t able to stop the conversion. After watching all the swing gate plays what struck me was that the greater athleticism of NFL players seems likely to make successful conversions from this gadget formation much more unlikely than at the college level. If you’re going to go for two is this the way to do it?

    Anon’s question and the response illustrate the nebulous advantage that a successful two point conversion brings early in the game. Early on, the biggest advantage may be a gain in momentum. That’s difficult to measure and you’re risking losing momentum if the try fails. A critical factor in the decision to go for two has to be a assessment of a team’s chances for success. The league average may be 50% success but some teams personnel against that week’s opponent are going to significantly increase or decrease those odds.

    I strongly suspect that we won’t be seeing a lot of teams going for two early in the games anytime soon. Fans and the press have brilliant hindsight. Any time that a strategy that is this unconventional fails and ends up having an effect on the outcome of a game the coach will be roasted regardless of the merits of the decision. This is the kind of thing that people remember and gets coaches fired and that’s something that most coaches try to avoid.