Push-pressure being exerted by the trail hand at impact

Question for John.

It is my understanding that you want the trail hand/palm to be applying a positive push-pressure during the later downswing and also at impact. Is that push-pressure being applied against PP#1 (located over the base of the lead thumb) or is it being applied against the aft side of the club handle below the coupling point at/near PP#3?

To some degree this would depend upon the length of the backswing… and how much wristcock and forearm rotation is being applied. For instance, with a short chip shot or putt, it might be different because there would be less range of motion to cover regarding forearm rotation or vertical wristcock (which should work in unison anyway)

I should have specified that I am only referring to a full golf swing action - specifically a driver golf swing action.

I would like to know where you think the trail hand should be applying a positive push-pressure - above, or below, the coupling point (mid-point between the hands) - and I would like to know what’s the purpose of applying that push-pressure with the trail hand during the later downswing and through impact?

Note that PP#1 (yellow area) in the following image is above the coupling point and the blue/green area on the aft side of the club handle is below the coupling point.



Hitters and swingers would be different… very different.
Think about VJ’s right hand coming off the club at impact… not much push there if any…
However, as a core driven hitter, the main power is coming from the pivot rotation, torso and that ultimately would be shoulders, because that is where our arms are attached to the rotating shoulders. If we rotate our shoulders level, then both arms are applying pressure to the clubshaft via the hands. I feel fairly equal pressure in both hands and the argument I have heard that you can’t push and pull at the same time is utterly false. Anywhere the skin on my hands is in contact with the grip of the club, I could be pressuring the shaft at that point because as a hitter, I am gripping firm and making sure my connection to the club is actively dynamic and prepared to resist any rotational torquing of the shaft that might happen due to an off centered hits. Playing good golf is a lot more about minimizing the negative results of poor shots, not as much about how many perfect shots. If I hit a 3 iron inside 10 feet three times in the round… I could still miss those putts and shoot the same score as if I got up and down from 30 yards. If I hit three shots out of bounds… that’s going to increase by score by 6 shots, and maybe more if you consider the impact that might have on confidence moving forward.


You state that you are using a positive push-pressure applied by the trail hand at impact to prepare to resist any rotational torquing of the shaft that might happen due to off-center hits. That would work if the twisting of the clubhead due to the GEAR effect of an off-center hit could be positively affected by any grip force being exerted at the level of the club handle. However, it is my understanding that the clubhead acts as a “free body” at impact and that there is no scientific evidence to show that the clubhead will twist less if there is more “force” being applied by the hands on the club handle at impact. In “The Search for the Perfect Golf Swing” book, Cochrane & Stubbs produced a golf club with a hinged joint just above the hosel, and they noted that there was no difference in the quality of ball striking between the hinged golf club and a regular golf club.

It is also my understanding that you want to continue to have “shaft flex” throughout the entire downswing to impact and that this “shaft flex” phenomenon implies the presence of i) lag tension and also ii) clubhead acceleration at impact.

TMG-literalists harbor that same opinion as expressed by Antony Taggart (aka the Swing Engineer) in this you-tube video at https://www.youtube.com/watch?v=oQUiJ9VgqQI

Do you agree with him that shaft flex at impact implies an accelerating clubhead, which he believes is necessary for a solid ball strike?

There are two problems that I have with that “belief”. First of all, a study of PGA/LPGA tour golfer driver swings showed that the “average” maximum clubhead speed was reached at ~94% of the downswing, and that the clubhead was decelerating slightly in the last 6% of the downswing.

Here is an example - featuring Rory McIlroy.

Kinematic graph of Rory McIlroy.


Rory’s driver clubhead speed graph (brown graph) is on the left and it shows that he reaches his maximum clubhead speed just before impact, and there is a plateau in the graph’s slope just before impact.

I have also noted that Rory McIlroy’s peripheral clubshaft is bent forward (and not backwards) between P6 => P7 in his driver golf swing action - as can be seen in these capture images from his driver golf swing action.

Note that Rory’s peripheral clubshaft is bent backwards (implying the condition of" shaft flex" and lag tension) at P5 (image 2) and at P5.5 (image 3) but that it is bent forward starting at ~P6. When Rory reaches impact, his peripheral clubshaft is bent forward (and not backward, which implies “shaft flex” and the condition of lag tension). I have never seen a PGA tour golfer come into impact with “shaft flex” (backward bend of the peripheral clubshaft) when swinging a driver. What happens in your driver golf swing action? Could you please post a slow motion of your driver golf swing action so that we can clearly see whether you have “shaft flex” (backwards bend of the peripheral clubshaft) all the way between P6 => P7.

Bertie Cordle is also a great believer in the idea of maintaining lag tension throughout the entire downswing and here is his image showing his hand couple scenario near/at impact.


Bertie believes that a positive hand couple scenario must exist at impact to ensure the presence of lag tension and forward shaft lean. To achieve that goal, lag pressure must be exerted by the lead hand in an away from the target direction (see green arrow) while the trail hand must simultaneously be applying lag pressure in a targetwards direction (see green arrow), and that combination represents a positive hand couple scenario, which will promote a counterclockwise torque around the coupling point (midpoint between the hands) at the exact moment of impact. Do you agree with Bertie Cordle that a positive hand couple phenomenon must exist at impact?


I did a video recently for an instagram post that should explain this all better… about torquing and off centered strikes… and how this can be controlled significantly with certain grip pressure protocols.

Rory’s swing isn’t set up to hold shaft flex. He’s opening up too soon and spending his rotational reserve on the downswing. He’s not closing the clubface relative to the target with pure pivot rotation like Hogan did (for example) As soon as you see a player straightening their right arm through the strike, they are using that as a mechanism to assist because the pivot isn’t working as efficiently as it could. This doesn’t mean you can’t play great golf… but there is just more timing involved and if you are playing and hitting balls all the time, it’s a viable method. Holding shaft flex is not an easy thing to do by any means. I don’t always do it either, and have been guilty of throwing some right elbow at the ball… but it’s not ideal, and when I am really keeping up with my conditioning, I can do it no problem.

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Here is video on how grip pressure can affect clubface torquing through impact.

Holding Shaft Flex

Jeff, it’s great to have ABS back online and nice to see you here posting again. We have had many interesting discussions over the years and your input and articulation is always appreciated!

I think with this 16 ounce persimmon driver, you can see how things are accelerating properly into the impact strike. It’s much easier to hold shaft flex with a monolithic persimmon that is just so hard to get it moving from transition. Easy to keep applying pressure all the way down and through the strike when there is so much mass in the clubhead. Moe used a 16 ounce driver. Told me George did also for a time… and also Hogan. As a science person, you would know that given or comparing two golf clubs traveling the same speed, the one with more mass is going to compress the ball more. It’s just common sense.

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I do agree completely with what he is saying… however, VERY FEW golfers do this… even the vast majority of PGA Tour players are not doing this. What he is describing and I agree is that this is more of the highest ideology of what we should strive for, and when it is actually attained, we are talking the stuff of the greats. Why not try? I do…

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Again, this sounds accurate… and I would suggest that that extra 6% that is decelerating is the difference between the best players on tour and a striker like Hogan or Moe. There is a difference, and it looks like someone might have nailed it down with some scientific data. Sounds right to me.

Often these kind of data collections are of mediocre tour players or just good amateurs around someone’s local golf club. The greats are different, and an extra 6% of acceleration would be significant and tangible.


If you are really capable of “sustaining lag” between P6 => P7 using your “holding shaft flex” technique in your driver swing, it would have huge repercussions because it would call into question the legitimacy of Kwon and Sasho MacKenzie’s explanation of the forces/torques causing the club release phenomenon (= release of PA#2) in a skilled pro golfer’s driver golf swing action.

Let’s look at some of the “evidence”.

I will start off with Ben Hogan’s driver swing action by using the slowest motion film (converted to video) that is apparently available.


Here are capture images of his late downswing.


Image 1 is at P5.2 and the peripheral clubshaft is bent backwards, which indicates that he is “sustaining lag”.

Images 2 and 3 are at P6.3 - P6.5 and it looks like the peripheral clubshaft is bent forward, which according to Kwon/Sasho MacKenzie (SMK)/David Tutelman indicates a negative hand couple torque scenario and the absence of a “sustaining lag” phenomenon.

Unfortunately, we do not have slow motion videos (at frame rates >1,000 frames/second) to be certain of what is really happening in Ben Hogan’s late downswing.

So, let’s look at your golf swing action.

Here is one of your videos on “holding shaft flex”.


Here is a capture image from that video.


My visual impression is that the peripheral clubshaft is bent slightly forward, which indicates that you may not be “sustaining lag” at the P6.5 position.

Here is another one of your “holding shaft flex” videos captured at 1,000 frames/second.


Here is a capture image from that video.


I have drawn a green line down the proximal clubshaft. I then drew a small green circular marker at the peripheral end of the green line and another one at the hosel of the clubshaft. I joined the two green circular markers with a red line. The red line looks to be tilted forwards to a very small degree suggesting that the peripheral clubshaft may be bent forward and that indicates a small degree of loss of the “sustaining lag” phenomenon.

Now, here is a capture image from your instagram video where you are swinging a 16 oz persimmon driver.


This capture image suggests that your perpiheral clubshaft is bent back slightly, which suggests that you are successfully “sustaining lag”. That’s amazing! I have never seen a pro golfer get to that ~P6.7 position with a driver swing and have the peripheral clubshaft bent backwards.

It really suggests that you may be capable of “sustaining lag” with your driver swing.

I suggest that you produce a high quality swing video of this same driver swing action (at a frame rate of 1,000 - 4,000 frames/second) and post in on you-tube. That would allow me to download the video in order to use my swing analyser program to view the video one frame-at-a-time so that I can determine whether you can successfully “sustain lag” throughout the entire P6 => P7 time period.

If you can successfully “sustain lag” between P6 => P7, then Brendon should introduce you to Dr. Kwon so that can he perform “inverse dynamics” modelling of your driver swing action to determine whether you are capable of sustaining a positive trail hand couple torque to well beyond P5.5.

Here is Kwon’s image of the torques been exerted by pro golfers and skilled collegiate golfers when swinging a driver.


The red graph (showing one standard deviation) is the hand couple torque graph, which is positive in the early downswing but it becomes negative after P5.5 in all those skilled amateur and pro golfers. Your “holding shaft flex” technique may be enabling you to have a positive trail hand couple torque to well beyond P5.5 and well into your late downswing, and it could be very informative to see what your trail hand couple torque graph looks like.

I also would like to see Kwon (or SMK) perform an instrumented grip study on your driver golf swing action. Although David Tutelman questions the legitimacy of instrumented grip studies ( see https://www.tutelman.com/golf/swing/openloop.php ), an instrumented grip study could be very informative in your specific case. I would particularly like to know how much push-pressure is being exerted by your trail hand at PP#1 (which is above the coupling point) and on the aft side of the club handle at PP#3 (which is below the coupling point) during the P6 => P7 time period.

Your video showing how light/firm grip pressures can affect the ball flight pattern of a toe hit is also very interesting. I would like to see you repeat that performance at different clubhead speeds using an instrumented grip, which could actually measure your grip forces being exerted in different planes (relative to the clubshaft).

I find your “holding shaft flex” technique intellectually fascinating and I would like to see golf researchers study your driver golf swing action in great depth, so that we can better understand what is actually happening at the level of your hands where it interacts with the club handle.


Jeff, could it be that what you’re interpreting as possible forward bend of the shaft may instead be toe droop? Same for the prior video of John that you referenced, as well as those of Hogan?


That’s a good question. It may be due to a toe droop phenomenon - especially considering the fact that he uses a clubhead of greater mass than the standard clubhead mass.

I don’t have the knowledge of how to exclude that possibility.



Jeff, it can be done… of course…
A short swing starting slow and then accelerating… it’s easy… easy as pie.
The longer the swing gets, the harder this becomes… so at what point does it become a cumbersome effort? For me… it depends. It depends upon the condition of my golf swing… how much I have been training and that my swing is sequencing correctly… for more full swings. In this still you have here, I am swinging a 16 ounce driver. HEAVY!! Really heavy club that I had to make myself. No stock persimmon even in the 50’s or 60’s came that heavy. Too heavy for most to swing. However, when I met Moe Norman and got inside his world a little bit, Moe was gaming a 16 ounce driver. The one pound golf club… he would say. He also said George Knudson gamed a 1 pounder. He said Hogan did also for a time. There are conflicting sources on this and I think Hogan said he swung a 14 ounce in Power Golf Book. But doesn’t mean he didn’t later game something heavier… we don’t know. I have been through quite a number of drivers myself. What I do know is that it would be harder to accelerate a heavier club initially… from transition… and know that I have been really picking apart Hogan’s swing techniques… I know A LOT MORE than I did 10 years ago. I worked with a student today on the deck and he is the first one that has come here for the course I will be presenting. I think he was pretty blown away by the discoveries I presented to him. Everything I have learned about Hogan is that he did things differently. VERY differently… different than me and everyone else. But I am chipping away at it and getting it. I’ll post a swing here and this clip above is from the “Hogan” swing technique. Interesting that it’s showing a held shaft into the strike. Now this is not easy stuff to do… not for the faint of heart. VERY demanding stuff. I am also in a 58 year old body… so it’s getting tougher each year. I’m still capable and in good shape generally, but the clock is ticking. I will say this… the way Hogan uniquely transitioned the clubshaft has everything to do with these objectives (holding shaft flex). It’s not surprising that the greatest striker was doing this. The greats do that little something different that makes them great. So looking at what other players do… it’s not necessarily the highest bar or marker of human excellence and possibilities. What we are talking here is “holy grail” stuff (of the golf swing)

I think they are testing players with swinging releases… so within that context, they are right. I don’t see any great hitters anymore… not in the light of Hogan, Knudson, Trevino. I don’t see it. Personally, I don’t think the modern drivers as light as they are, going to get there (holding shaft flex) because they are just too easy to accelerate quickly from the top… and if a player is really going at it hard, I am pretty sure they are reaching maximum velocity way before impact…zeroing out acceleration. The science is doing a great job of figuring out how to best hit the ball far. I will give them that. But straight? I don’t think so. Barking up the wrong tree on that one. I want to be long, which I am relative to the classic game, but more important is that I am straight. This gets into the bigger questions about golf in general. Suppose a player shoots 72. How many times during that round is the player trying to hit the ball as far as possible? Not putting, not chipping, pitching or iron shots. Not the par 3’s. Not any lay up par 4’s. So maybe 6 or 8 times a round? That’s it. Out of 72 shots… only 6 or 8 would have the MAX objective. The rest of the game is about accuracy and controlling distances… not all out flailing at the ball as hard as possible. Hogan would have known this, and would have designed his swing to gain advantage over the field. I firmly believe that.

The scientists have looked at ROC (rate of closure of clubface) to find out if there is any correlation with shot dispersion. Check out this article by Dr Sasho MacKenzie and the research done by Ping and Dr Phil Cheetham.



Still a lot more research required because there are other factors that could obscure these results as Dr Mackenzie stated in his article.

Does Rate of Closure actually matter?
It would seem beneficial to be on the low end of the Rate of Closure spectrum. Wouldn’t it be tougher to ‘square-up’ a faster closing face? However, there is currently no evidence to suggest that players with lower RoC hit more fairways or hit their approaches closer to the hole. For example, in his PhD Thesis, Dr. Phil Cheetham found no relationship between shaft twist speed and driving accuracy in a group of 70 PGA Tour players. In the studies that have been conducted, it is possible that the influence of RoC was obscured by other golfer characteristics, such as hand-eye coordination and course management.

I am however going to ask Dave Tutelman about how a loose/firm grip pressure might affect how the clubface deflects for an off-centre hit.

I saw John Erikson’s video demonstrating how the clubface with a loose grip opened up considerably during impact for a toe strike, sending the ball to the right. This seems to contradict what I’ve read on Dave Tutelman’s website that anything done by the hands on the grip (ie. PP3 to help keep the clubface stable through impact) does not have time to affect the clubface rotation through the impact compression period (which is very short for even a full driver swing - about 0.4 msecs or 4/10,000 of a sec).

Well, I am by nature very suspicious of scientists making claims about golf swings, ball flight etc. The reason is, I am a player and I am going to trust my direct and personal knowledge and experience over someone else’s conclusion based upon “science”. Science is a process of inquiry and discovery, testing, retesting and hopefully moving toward truth.

In this simple example of hitting a ball off the toe of the club with a firm grip vs a light grip…it’s clear as day that the firm grip has less clubface rotational twist. Of course this is true… as a player… sure. No different that hitting out of thick rough around the green. I am not going to dig that ball out with a light grip. The club will get snagged on the grass and stop or twist the clubhead. I am going to grip it very tight, and bulldoze through it playing for the ball to come out hot. If I am tough enough, it will. So when a scientist says it doesn’t make a difference etc… well, that’s just not true, and it starts to become opinion that is based upon some kind of incomplete data collection. Take another example… I toss a volley ball at a window, then I toss a bowling ball at the same window. I say it makes a different sound! Same thing with Trackman. The machine is only looking at the ball characteristics then reverse engineering to say… this is what the club must have been doing. Yet Trackman has no idea what the mass of the clubhead was, no place to input that data… and acts as if that would not be a determining factor. It’s a very incomplete picture. I think science will get there, and I could tell them what they need to be looking at from a good players point of view, but until then? I don’t see it having much to offer really. The machine doesn’t even know where I am aiming… or whether or not I am holding shaft flex, or what the pressure in my hands would be whether or not I am using a swinger or hitter’s release.


Do you know of any present-day pro golfers who are using your “holding shaft flex” technique?

Could you please provide me with the names of a few examples so that I can evaluate their golf swing action?


I haven’t seen anyone doing it… none that I know of… but there might be… I just haven’t seen it. What I have seen is that most are accelerating lightweight gear too quick from the top and rotating their torso and hips too early to possibly keep flex on the shaft into the strike.

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