Knowing Too Much About Your Swing Can Make You Worse: Reading Jamie Mulligan's Advice Through Data

A golfer stood over the ball for fourteen seconds.

I timed him with my phone, not to catch him out, but because elapsed time from grounding the club to the club moving is the only thing in that Saturday morning at a driving range outside Binh Duong that can actually be measured. He plays off 14, was in the qualifying round of his club's open championship, hole 7, 152 metres to the flag, crosswind from right to left. In those fourteen seconds I counted three separate adjustments of his right hand, one crouch to check the clubface, and one muttered phrase I assumed was “don't roll the wrist.”

The ball came out low, hit the front fringe, and rolled down the far bank.

What interested me was his reaction. He turned to me, laughed, and said the sentence I have now heard at more than twenty different golf courses: “I was thinking too much.” Nobody checks that sentence. Nobody asks whether removing the three thoughts would have produced a better shot, or merely a different one. He had just delivered a diagnosis of himself that could not be wrong. That is why I stop at sentences like that.

Later that morning I rewatched footage of a professional round on my phone. A player ranked around thirtieth in the world stood behind the ball, looked at the target, and completed the swing roughly 1.2 seconds after starting his takeaway. His total pre-shot time was shorter than the time the amateur spent on his second hand adjustment.

The distance between those two images is what this piece is about. And it has just been put on the table by one of the most credentialed teachers in the United States.

What Mulligan's article says

GOLF.com published an instruction piece by Jamie Mulligan, a PGA Professional, a member of the GOLF Top 100 Teachers list, and the coach of Patrick Cantlay on the PGA Tour and Nelly Korda on the LPGA. His central claim: the volume of swing information an amateur absorbs today has outrun his capacity to digest it. Footage of every elite swing sits in a pocket. Thousands of free instruction clips. A three-dimensional model of a “correct” motion retrievable in three seconds. Mulligan hypothesises that this abundance may be net negative.

His phrasing is worth quoting directly: the more a golfer understands about their swing, the more opportunities they have to interfere with it. Understanding becomes surface area. Every piece of knowledge is somewhere for the hand to grab a system that should run itself.

From there he describes a familiar pattern: the player who practises beautifully, walks to the first tee, has one technical thought, hits a poor shot, and loses faith in the swing within two holes. He proposes a reattribution of cause — the problem may not be the mechanics, it may be the conscious control of the mechanics. The fix is a three-step routine: see it, feel it, trust it. Pick the target, pick the shot, pick the intention, then let muscle memory take over. He calls that state “being in it,” and he calls the competitive moment “the party.”

The article reads well. It has the voice of a man who has stood on tees with great players and knows what he is talking about.

And it contains no numbers at all.

No strokes gained. No dispersion data. No tournament results. Not a single measurement of the phenomenon it describes. All 27 information points in the source deconstruction are attributed either to nothing or to the author himself. That is where my analysis starts, and it is what I have to state plainly before praising or criticising: we are assessing an argument supported by professional authority, not by evidence.

A correct principle with no evidence behind it

Mulligan's mechanism is not his own invention. It maps almost exactly onto a branch of motor-learning research that has existed for decades: the distinction between an internal and an external focus of attention. Beginners benefit from thinking about the body. Skilled performers are harmed by it and benefit from thinking about the target.

I am not quoting effect sizes here, because I do not have a direct citation in hand and I will not turn a correct principle into an invented number. What I can say with confidence: the direction of the argument is right, and it is not new. What is new is that it appears on a consumer-facing media platform, attached to the name of a Top 100 teacher and two elite students.

Data does not lie. But reputation whispers into the ear of the person who never reads the table.

Set that aside for a moment. In professional sport, a correct argument presented without data can still be a good argument, provided the reader knows what they are receiving. The problem with this article is not the absence of numbers. The problem is that it offers a diagnosis the reader has no way of testing against themselves.

Two modes: building a swing and playing a shot

The most technically valuable passage in Mulligan's piece is the separation between developing a swing and playing a shot. This is where his argument stands up, and it stands up for a reason he never states: those are two different learning tasks with two different optimal attentional states.

Building a swing is skill acquisition. It needs feedback, repetition, volume, and conscious intervention. You have to think about the left wrist. You have to think about the hips. You have to place a stick on the ground to check the path. There is no other way to change a movement pattern.

Playing a shot on the course is skill expression. It is single-trial, consequence-laden, and it runs on processes loaded in advance. Here conscious intervention does not improve the outcome; it consumes the bandwidth needed to calculate distance, read wind, and select a landing point.

Mulligan says the best players know when to switch modes. That is the most precise sentence in the piece, and the most buried.

Why does it matter for amateurs in Vietnam? Because most practice sessions I observe at courses around Binh Duong, Dong Nai and Ho Chi Minh City blend the two modes. A player arrives, hits 80 balls in 40 minutes with a different thought on each, then walks to the first tee carrying the last three. No technical block. No separate practice round. Both modes run concurrently, and neither runs well.

The 60-ball test and its limits

If I had to test Mulligan's thesis against one specific amateur, this is the minimum design I would use.

Pick a single shot, say a 7-iron to a fixed 150-metre target. Hit 30 balls under condition A: target only, no technical thought, the see-feel-trust routine. Hit 30 under condition B: carrying the two technical thoughts the player believes are necessary. Record where each ball finishes with markers, or with a monitor if the facility has one. Compute the lateral standard deviation and the distance spread.

The output to read is not which ball finished closer to the pin. The output is the shape of the cloud. If condition B produces a narrower cloud offset to one side, the technical thought is doing useful work — it is correcting a fault. If condition B produces a wider cloud on both sides, the thought is destructive. Those two results lead to opposite conclusions, and there is no way to distinguish them by watching a single poor shot on the course.

Now the honest part. Thirty balls per condition is the absolute minimum, and it is still too few. The variance in golf shots is enormous; one 60-ball session can be dominated by fatigue, order effects, hitting off mats rather than grass, or wind shifting between blocks. To reach a defensible conclusion you need at least three sessions on different days, alternating the order of A and B, with conditions logged.

And that is precisely the point. The advice to trust the swing you have built cannot be verified by the person receiving it. They must either believe it or ignore it. There is no third path.

Which metrics are missing

In my analytical frame, a golf game is read across four groups: off the tee, approach, putting, and around the green. Mulligan's article touches none of them. It is a layer over everything, locatable nowhere.

That means the piece cannot be tested with strokes gained, because strokes gained measures outcomes while the article describes a process. To build evidence I would need a different metric: process-adherence rate, measured as the proportion of shots where the player completed all three steps without adding a fourth. That is measurable with a phone and a notebook. Nobody does it, because it is not attractive.

The article is also entirely course-agnostic. No grass type, no green speed, no terrain. For a mental-game piece that is reasonable. It also means the advice has never been checked against any specific condition — including conditions in Vietnam, where greens are slower, grasses differ, and monsoon wind matters far more than a reader in the United States would picture.

Based on my experience watching amateur rounds in Binh Duong and Dong Nai, I see a recurring pattern: Vietnamese golfers import the mental framework of the American tour without importing the measurement infrastructure that comes with it. They learn to think about dispersion, carry distance and clubhead speed, but they have no ShotLink, no on-course tracking, and often no long-term coach. They carry the language of data without the data. That is exactly the environment that breeds the phenomenon Mulligan describes.

Data does not lie. It also does not arrive on its own.

The boundary the article never draws

This is where I part company with Mulligan, and I part decisively.

The see-feel-trust routine is an intervention on delivery, not on technique. It improves how you take an existing motion to the course. For a player with a genuine mechanical defect — a path that is off, a face that closes, an uncontrollable two-way miss — committing harder to the target produces a more consistent version of the same flaw. Not a correction. A systematisation.

The article acknowledges this indirectly by locating technique work on the practice tee. It never states the boundary condition. That condition matters, because it determines who should listen.

My classification is simple. If you have one miss that repeats in one direction — always left, always right — the problem is mechanical, and you need a technical block, not more commitment. If you have two misses in opposite directions appearing at random — left, then right, unpredictably — the problem is process instability, and Mulligan's advice applies.

Those two symptoms look identical on a scorecard. They have completely different causes and completely different fixes. The article provides no tool for telling them apart.

There is a second risk I have seen in practice: applying the advice mid-overhaul. During a swing change the new pattern is not yet stable under pressure. Abandoning conscious rehearsal too early stalls the change halfway. For that group, committing to the target is a very efficient way of reverting.

The paradox of the teacher with the machines

There is a detail in the piece that a fast reader will miss, and it is the most interesting one logically.

Mulligan is a PGA Professional specialising in swing biomechanics. His professional toolkit includes 3D motion capture, force and pressure plates, high-speed video and launch monitors. He earns a living measuring the golf swing at the highest resolution technology allows.

Simultaneously, he writes an argument that understanding more about the swing makes it worse.

On the surface that is a contradiction. In substance it is not, provided you draw a line the article never draws: coach-facing diagnostics versus player-facing in-round cognition. A 3D system is not for a golfer to think about on the first tee. It is for a coach designing a practice block. Those live at different points in the week.

Because the line goes unstated, readers can draw the wrong conclusion in both directions. One abandons measurement entirely — wrong. Another keeps carrying numbers onto the course — also wrong.

For the Vietnamese market I think the second risk is far larger. Launch monitors are now present at many ranges and indoor studios, and hourly rental has fallen to a level an average amateur will accept. Vietnamese golfers are roughly where American golfers were fifteen years ago: the technology has just become reachable and nobody has taught them how to read it. Practice sessions turn into a contest between parameters.

Patrick Cantlay, a stopwatch, and an unmeasured gap

Here I think the article has a hole its author did not see.

Mulligan uses Cantlay and Korda as reference cases for his method. He says nothing about either player's form, results, ranking or technique. The two names appear immediately before the method is explained, and their function is a credibility bridge. That is legitimate journalistic shorthand. It is also an unestablished causal arrow: there is no evidence that the method produced those players' results.

But the deeper problem is Cantlay.

The “being in it” state Mulligan describes — selecting the target, selecting the shot, committing to the intention, then letting the body work — is an internal commitment state. It is not a fast one. Deep commitment takes time: time to pick the target, time to visualise the flight, time to visualise the landing area, time to discard alternatives. Not one step in that routine is designed to save seconds.

Cantlay has repeatedly been criticised publicly for slow play, widely reported in the international golf press. Mulligan's article does not mention time once.

I need to be precise about confidence here, because this is where analysis slides into inference. That Cantlay has drawn public slow-play criticism is a matter of public record with high confidence. That Mulligan's routine causes it is inference, and I have no timing data to support it. Nobody publishes his average pre-shot seconds by season. Nobody correlates that number with coaching changes. That is a data gap, and I will not fill it with speculation.

What I can say is this: an instructional framework that describes deep commitment without a time budget is an incomplete framework. For amateurs the consequence is not a slow-play penalty — almost nobody is penalised in amateur events. The consequence is a broken rhythm, and a broken rhythm affects all four players in the group.

There is an interesting reverse scenario. If the real cause of slow amateur play is the re-check loop — stand up, step back, stand up again — then committing decisively to a single target can shorten pre-shot time. Commitment replaces doubt, not speed. In that scenario Mulligan's advice improves pace rather than harming it.

Three scenarios, three opposite conclusions, and no data to choose between them. That is the actual state of this entire subject.

Nelly Korda and outcome bias

Using Korda as an example carries its own methodological problem.

A coach is credited with a student's peak run precisely when the student is winning. The same method is rarely invoked to explain a slump. That is textbook outcome bias: sampling after knowing the result.

To test it seriously you would do the reverse. Take every student a coach has worked with in a given window, successful and unsuccessful, and compare rates. Nobody does this in golf, and nobody does it in football, where I come from. Transfer models and coach evaluations make the same error: they overrate young potential and underrate dressing-room chemistry. In golf, the underrated variable is the fit between the teacher's language and the player's way of receiving information.

I am not saying Mulligan's method does not work. I am saying we have no way of knowing, and citing two famous names does not change that.

Two different credentials

The article uses two kinds of certification. The first is PGA Professional — an occupational classification of the PGA of America with a real education and examination pathway. The second is GOLF Top 100 Teacher — an editorial list selected and published by GOLF.com, which also published this article.

Those are not institutionally equivalent. One is a professional certification. One is a media ranking. The article uses both as if they were the same, and the owner of one of them is the publisher of the article.

That is a structural conflict of interest, not an accusation. It is worth naming because it explains a real loop: a teacher is ranked, writes on the ranking owner's channel, attracts clients, produces results, gets ranked again. The loop feeds itself. It does not make the method wrong. It makes the method harder to evaluate.

For Vietnamese readers, read the credentials this way: PGA Professional is information you can verify through an association. GOLF Top 100 is information you can verify through a magazine. Different levels of reliability, and distinguishing them is the reader's job, not the author's.

The final paradox: the article argues against itself

Mulligan's piece warns about the abundance of golf instruction content. It is part of that abundance.

No single article resolves this. The anti-overthinking genre has become a product category. It is not a counterweight to technical content; it is a branch of the same stream. The reader consumes one more piece in order to learn how to consume less, and ends with more information than they started with.

I am not outside this paradox. I wrote this. If you have read this far you have absorbed several thousand more words on why absorbing too many words is harmful.

The only exit is not to stop reading. It is to turn reading into a filter with criteria: does this piece give me a test I can run on myself within a week? Mulligan's article passes on process — see, feel, trust is runnable today — and fails on diagnosis, because it gives you no way to know which group you are in.

Who actually benefits in Vietnam

The advice to trust the swing you built in practice assumes a material condition: that you have a swing worth trusting, and enough repetition volume to have built it.

In the United States that assumption usually holds for the person reading a golf magazine. In Vietnam it holds for a much narrower segment. A player hitting 40 balls a week at a nearby range, with no coach, learning from video, does not have a stable movement pattern to trust. For that player, committing to the target is committing to a random swing.

Conversely, a player with regular access, a coach tracking them, and a reasonably stable pattern who is paralysed by too many technical thoughts — that is the person the article targets, and for them the advice has real value.

That split matters because it turns a universal piece of advice into a conditional one. And conditional advice should be stated with its conditions.

I dislike uncertainty. But I have learned that one unanticipated variable can be stronger than any algorithm, and that variable is usually a material condition the writer cannot see because it is too familiar to them.

What I take from this article

Not the sentence “stop thinking so much.” That sentence is useless to someone who is already thinking too much, in the same way that “don't worry” is useless to someone who is worrying.

What I take is the separation of two modes. Building a swing is conscious work with measurement and feedback, and it belongs in its own block of time, never blended into a round. Playing a shot is a performance task that requires a different attentional state. Good players are not the ones who think less. They are the ones who know which mode they are in.

And the second thing: if you intend to apply any mental-game advice, spend 60 balls testing it first. Thirty target-only. Thirty with two technical thoughts. Measure lateral and distance spread. Write it down. Repeat next week with the order reversed.

You will not get a statistically robust result. You will get something else: knowing whether your miss is one-directional or two-directional. That is worth more than any instruction article, including this one.

I do not predict. I read the data and accept the consequences.

The signal I will watch in the next cycle is not how many more pieces get written about thinking less. It is whether any golfer in Vietnam starts carrying a dispersion notebook to the practice ground. When that happens, the argument between trusting the swing and understanding the swing ends on its own, because the player will have the one thing both sides lack: their own data, measured on their own course, under their own conditions.

Data does not lie. It stays silent until someone bothers to write it down.