If you've watched Benny Feilhaber take penalty kicks for Sporting Kansas City over the past two seasons, you have surely noticed that dragged-foot stutter step that has become a trademark of his approach to those pressure-packed moments.
That slow-motion move isn't simply for show, or to psych out the goalkeeper (trust me, as a goalkeeper, we usually aren't terribly fazed by spot kicks; we know the pressure is on the kick taker, not on us). It is a fishing technique, a way of gaining a crucial piece of information: where the goalkeeper intends to dive to try to save the penalty.
Penalty kicks are unique in that they force goalkeepers to be explicitly proactive rather than reactive to save a given shot. Generally, goalkeepers are proactive in other ways--using their positioning to make saves easier, directing defenders to shade an attacker a particular way, that sort of thing. But ultimately, where the shot ends up going is up to the shooter.
That remains the case for penalties, but because of the close quarters and high velocity of those shots, goalkeepers are forced into what is popularly called a "guessing game" but in truth is anything but. As Simon Kuper and Stefan Szymanski wrote extensively about in their seminal work Soccernomics, both goalkeepers and kick takers use elements of psychology, past tendencies, and game theory to try to up the odds in their favor. (This is in addition to real-time cues like body language).
This gives goalkeepers a number of tools to use in their efforts to increase their chances of saving any given spot kick. Since they are the ones who must choose, before the ball is kicked, exactly what they are going to do to have much of any opportunity of saving the spot kick, it creates a role reversal for the shooter--they can, if their skills allow for it--react to the keeper rather than the other way around.
Send em' the other way.
The lateness of Benny's stutter step achieves this. Years ago, you might see stutter steps earlier in a player's run-up (think of Cristiano Ronaldo's own approach to penalties when he was with Manchester United), but as is the case in genuinely competitive enterprises, goalkeepers began to adjust and stay still even later to negate any information-gaining advantage procured by the stutter step. CR7 is again a good example--as Kuper and Szymanski noted, CR7 almost always went the same way whenever he took that stutter step, which negates almost the entire information-gathering value of the technique. If you're going to go the same way regardless, why interrupt your run-up?
Feilhaber takes a fundamentally opposite approach to his spot kicks. If you were to look at clips of his spot kicks one after the other, he takes his stutter step as late as humanly possible in order to force the keeper into showing his hand first, and then *always* places the ball away from the keeper's movement. The advantage is obvious: when you know where the keeper is going, you don't have to worry about using power to beat the keeper, and instead can focus solely on accuracy.
The difficulty of facing this sort of run-up as a keeper is tough to understate: unless a keeper has a Hakeem Olajuwon-esque wingspan (little known fact: he played soccer as a keeper prior to making a storied career for himself in the NBA), they *have* to dive rather than simply reacting to the penalty kick's trajectory, otherwise a clinical shooter will beat them 100% of the time by simply placing the ball just inside one of the posts, and with enough power, the ball will always arrive there before a keeper's hands do.
Contrast all of this with the other player who regularly takes spot kicks for Sporting: Dom Dwyer. Dwyer, true to form, relies on power at least as much as placement, and because he takes a proactive rather than reactive approach (meaning he chooses his shot placement prior to ending his run-up), he runs the risk of telegraphing his shot--something that has led to his spot kicks being saved in the past.
Perhaps the most instructive example of contrast in Dwyer's approach and Feilhaber's approach is that epic 11-round penalty shootout that took place last autumn in Portland during the 2015 MLS Cup playoffs. Feilhaber went first for Sporting--as any team's regular taker is often wont to do--and his kick was textbook Benny: run up, slow drag of the foot at the end, bait Timbers keeper Adam Kwarasey into biting, and calmly send the ball the opposite direction into the net for an easy goal.
Dwyer's miss got overlooked by the other misses, which were either more spectacular (Saad Abdul-Salaam's striking of both goalposts) or more boneheaded (Matt Besler's ill-advised attempt at a Panenka chip shot), but it, too provides a template for what often went wrong for him when taking penalties: his body language in terms of where his head, hips, and feet all added up to telegraphing his shot (if you freeze frame the video right as the ball leaves Dwyer's left boot, you can see his right boot pointed where the shot will go, with his hips opening up in that direction), and unless you place such a shot absolutely perfectly, a keeper can get to it even with power behind the shot, and that is precisely what Kwarasey did.
Dwyer's struggles from the spot highlight the difficulties inherent in the proactive approach: yes, you are still the odds-on favorite to emerge victorious from the one-on-one encounter, but it requires an ability to mask your intentions that some players are better at than others--and that some keepers are better at sniffing out than others. However, if you begin your run-up still not knowing which direction you will go--as Benny does--then there is no information to mask.
This is where game theory comes into play: if you know what a keeper is almost certainly going to do--that is, dive one way or the other--what do you do with that information? You could decide on a direction independent of the keeper, you could decide on a direction based on the keeper's own tendencies and history, or you could decide to act without knowing the end result of that action.
Benny has chosen the third of those options, and his success with this approach is undeniable: he is a perfect 11-for-11 from the spot (including in shootouts) for Sporting, and the lion's share of those goals have come using this reactive approach. Until MLS keepers find a way to adjust to Benny's technique (or unless FIFA decides to amend the Laws of the Game to ban it), he will likely continue to beat the already favorable odds for taking spot kicks. And whenever he is on the pitch, he needs to remain Sporting's default choice for taking penalties.