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Post by imperfectgolfer on Aug 27, 2022 13:56:33 GMT -5
Just found a youtube playlist of a golfer who used ABS 11 years ago and shows him practicing the various module drills. www.youtube.com/user/awdeangolfThe striking of the impact bag also reminds me of this old video showing Henry Cotton using a rubber tyre (instead of an impact bag) to develop 'educated hands'. I'm just wondering whether ABS modules are indirectly helping their students develop educated hands rather than achieve some of these unsubstantiated claims by JE. DG I don't see an connection between Cotton's "educated hands" teaching and the ABS technique, which teaches a "holding shaft flex" technique through impact using a pivot-induced acceleration of the hands through impact. However, although the ABs technique involves accelerating hands and a bent back peripheral clubshaft through impact, I have never seen it demonstrated in a full golf swing action. Their ABS modular demos show a much shortened backswing action that is combined with a virtually no clubhead lag starting position at P4. Jeff.
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Post by dubiousgolfer on Sept 1, 2022 17:47:37 GMT -5
Here is a copy of my final post on the ABS forum (before JE deletes it). _____________________ I was tempted to not post anymore on this forum which seems obviously anti-science but some of the criticisms levelled at me and others deserved one final response. Lagpressure posted this image of Greg Norman to prove shaft flex. Both the driver and 5 iron swing had the shaft flex measured using strain gauges. You can see that there is lead shaft flex for both at impact. JE needs to look at Erik Barzeski’s criticism of his claims on ‘The Sandtrap’ and have the courage to put his neck on the line rather than hide behind 2d images. thesandtrap.com/forums/topic/116727-john-erickson-advanced-ball-striking-in-2022/For that person who accused me (and Dr Mann) of being some wrx believers in the Monte Scheinblum’s ‘No Turn Cast’ technique, please look at this post I raised on the NGI forum where Dr Mann has done a critical analysis. newtongolfinstitute.proboards.com/thread/967/turn-cast-pro-golfers-doingI also wondered why JE deleted my post that showed a possible doctoring of one of the images he posted to prove shaft flex post impact (without striking a ball). That is also shown on the NGI forum if you wish to view it. newtongolfinstitute.proboards.com/thread/966/john-ericksons-ideas-swinging-hogan?page=2Or will JE delete this post too!!! --------------------------------- DG
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Post by dubiousgolfer on Sept 2, 2022 7:55:24 GMT -5
As I envisaged, JE has deleted my ABS posts of the 'edited' images without an explanation. I think he might be ashamed that he has tried to deceive people.
Most of those ABS posters are delusional in their strongly held beliefs and will never be convinced, no matter how much evidence is published about shaft flex.
DG
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Post by imperfectgolfer on Sept 2, 2022 18:00:21 GMT -5
As I envisaged, JE has deleted my ABS posts of the 'edited' images without an explanation. I think he might be ashamed that he has tried to deceive people. Most of those ABS posters are delusional in their strongly held beliefs and will never be convinced, no matter how much evidence is published about shaft flex. DG Many of those ABS-groupies (eg. AjersJJ) are emotionally infantile and incapable of rational thinking. John himself is surprisingly irrational and he cannot understand why we reject the value of this video where he claims to be demonstrating that he can "hold shaft flex" through impact. I am not disputing that he is "holding shaft flex" in that video. However, the video does not show where his end-backswing position is located and it doesn't show how much lag he has at P4. If he is starting his downswing at the P6 position with minimal clubhead lag, then he can apply a linear force with his two hands on the club handle that produces an alpha torque force that is parallel to the swingplane between P6 => P7+. If that force increases as it gets closer to impact, then he can easily "hold shaft flex" by ensuring that the club handle moves faster than the clubhead end of the club all the way between P6 => well beyond impact. However, that scenario is very different to his "real life" full golf swing action - as seen here. Image 2 shows that he has retained most of his clubhead lag until P5.5. Image 3 shows that he lost a lot of clubhead lag between image 2 (P5.5) => image 3 (P6.3), which means that there is another "club releasing force" in play (other than the linear force moving the club handle along the hand arc path) that causes the clubhead end of the club to move faster than the club handle end of the club and that causes the lead wrist to uncock. John and the ABS-groupies seemingly cannot understand the significance of that fact.
Here are capture images of Adam Scott's 3-iron swing for comparison. Image 1 is at his P5.5 position. I have drawn a blue ring over his clubhead. Image 2 is at his P6.3 position. I have drawn a green ring over his clubhead.
The red splined path shows his hand arc path between P5.5 => P6.3. Note the distance his hands travel between P5.5 => P6.3 and it is far less than the amount the clubhead has traveled during the same time period (as judged from an angular rotational perspective). If Adam Scott was handle-dragging the club handle between P5.5 => P6.3 while using the "holding shaft flex" technique then the lead wrist should not be uncocking.
Note that there is no difference in the degree of lead wrist uncocking happening between P5.5 => P6.3 in both of John Erickson's and Adam Scott's swings - and the presence of lead wrist uncocking means that there is a club-releasing force/phenomenon in play that negates the possibility of there only being a "pure" handle-dragging technique in play that allows the "holding shaft flex" phenomenon to be constantly present between P5.5 => P6.3 in an unchanged manner. Here are capture images from John Erickson's holding shaft flex video. Note that there is no lead wrist uncocking (club releasing phenomenon) happening between image 1 => image 3. Under those conditions, the only force causing the clubhead to move targetwards along its clubhead path is the force due to the hands moving targetwards along its hand arc path. If there is no club releasing phenomenon in play, then it is easy to "hold shaft flex" as seen in those capture images. However, how can a golfer claim to be "holding shaft flex" when the lead wrist is uncocking rapidly during the later downswing, which means that the clubhead end of the club is traveling faster along its clubhead path than the hands are moving along its hand arc path (from an angular rotational perspective)?
Jeff.
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Post by dubiousgolfer on Sept 3, 2022 21:42:36 GMT -5
JE has just posted another video with his full swing. Difficult to assess if he has shaft flex at impact so I magnified one of the frames just before impact. It's not an ideal angle but it looks like there is some forward flex but not very much. I'm unsure why he did a video of a swing which caused the ball to speed off the clubface almost along the ground. DG
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Post by imperfectgolfer on Sept 4, 2022 11:11:30 GMT -5
I have wrongly accused John Erickson of being a charlatan because he claimed that he can "hold shaft flex" throughout the downswing into the early followthrough, but I have never seen him accomplish that goal in a full golf swing action. Here are capture images from his full driver golf swing action where he tried to swing like Hogan. = First set of capture images.
You can see that he is "holding shaft flex" at P5.2 (image 1) and at P5.5 (image 2) but his peripheral clubshaft is bent forward at P6.2 (image 3) which means that he cannot be "holding shaft flex" during his later downswing. The clubshaft has also bypassed his lead arm between P7 (image 4) and P7.4 (image 5) which means that he cannot be "holding shaft flex" in his early followthrough. Until now, I have only seen him "hold shaft flex" in his later downswing/early followthrough when he uses an artificially shortened backswing action involving minimal clubhead lag at the shortened P4 position. However, his latest video shows him seemingly "holding shaft flex" during his later downswing/early followthrough when performing a full golf swing action.
Here are capture images from the video. = Second set of capture images.
Image 1 (nearing P6) shows that his peripheral clubshaft is bent backwards and he is very likely "holding shaft flex" at the this time point in the mid-downswing. I have not presented any capture images of his P4 => P5.2 time period, but if you look at his video you will see that he has minimal backwards bending of the clubshaft during his early downswing. That would suggest that JE is not accelerating his lead hand between P4 => P5.2 (like most pro golfers who are TGM swingers and as was also seen in that first set of capture images ) and that he is only earnestly starting to accelerate his lead arm motion starting between between P5.5 => P6. Note that his peripheral clubshaft is still bent backwards at P6.2 (image 3) which is very different to his P6.2 scenario in that first set of capture images and I can easily accept that he is "holding shaft flex" at his P6.2 position. I can even accept that he is still "holding shaft flex" at P6.6 (image 3) and at P6.9 (image 4) even though there may be minimal forwards bend of his peripheral clubshaft, which is likely due to the club releasing phenomenon (release of PA#2) which is happening in his later downswing. The amount of fowards bend of the peripheral clubshaft is very small between P6.5 => P7 and I can readily accept his claim that he is using a "holding shaft flex" technique at the level of the club handle in this particular full golf swing action. Image 5 is at P7.3. Note that the clubshaft has not bypassed his lead arm and note that the peripheral clubshaft is bent backwards. Both of those facts are compatible with JE's claim that he is "holding shaft flex" during his early followthrough. JE also claims that he is accelerating his lead hand throughout his later downswing and through impact when performing his "holding shaft flex" technique, but that fact cannot be confirmed by viewing these capture images. JE should really be willing to have a GEARS evaluation because it may indeed show that his claims of not decelerating his lead hand motion between P5.5 => P7 (as seen in most pro golfers who use a TGM swinging technique) is true. Even if a GEARS evaluation does not show that he is actually accelerating his lead hand motion through impact, it would be amazing to learn that he can avoid lead hand deceleration happening between P5.5 => P7. JE states that there would be travel expenses involved in having a free GEARS evaluation performed by Eric Barzewski in Pennsylvania, but he could crowd-fund his travel expenses. I would be willing to donate $20 to any crown-funding method of paying for his travel expenses, and I am sure that many other people would also contribute enough to totally fund all of his travel expenses.
I would also like to see JE being scientifically evaluated using an instrumented grip handle combined with pressure sensors being present at PP#1 (located over his lead thumb's base) and on the aft side of the club handle at PP#3. That could possibly confirm JE's assertion that he is applying a positive push-pressure with his trail hand against the aft side of the club handle and at PP#1 during his later downswing and early followthrough. That "fact" would really turn the golf instructional world upside-down and create a furor because many golf instructors claim that it does not ever happen in a professional quality type of full golf swing action. Jeff.
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Post by dubiousgolfer on Sept 4, 2022 17:42:57 GMT -5
Dr Mann I'm not convinced at all with that recent video JE posted. How do you know he was swinging at his normal full swing speed? He could quite easily have done the swing very slowly and recreated the conditions of an abbreviated backswing (just like his previous video). JE should have shown the video at full speed and then just run it in slow motion. I compared two images of the ball position post impact for approx the same hand/club position (also post impact) for different videos (see below where the right image is from his recent video). I know this is unscientific and he's not using the same club (the recent video is an 8-degree persimmon driver) but the ball has only moved half the distance as the swing in the left image. I also don't know whether both strikes were at the sweet spot but the ball hardly leaves the ground in his most recent swing. I don't think JE will take up the offer to be measured on GEARS, even if volunteers wish to pay for his travel costs. DG
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Post by imperfectgolfer on Sept 4, 2022 20:58:16 GMT -5
Dr Mann I'm not convinced at all with that recent video JE posted. How do you know he was swinging at his normal full swing speed? He could quite easily have done the swing very slowly and recreated the conditions of an abbreviated backswing (just like his previous video). JE should have shown the video at full speed and then just run it in slow motion. I compared two images of the ball position post impact for approx the same hand/club position (also post impact) for different videos (see below where the right image is from his recent video). I know this is unscientific and he's not using the same club (the recent video is an 8-degree persimmon driver) but the ball has only moved half the distance as the swing in the left image. I also don't know whether both strikes were at the sweet spot but the ball hardly leaves the ground in his most recent swing. I don't think JE will take up the offer to be measured on GEARS, even if volunteers wish to pay for his travel costs. DG Excellent comment! It could be that JE was swinging at a much slower speed so that he could demonstrate that he can "hold shaft flex" throughout his late downswing and early followthrough. Also, as you correctly pointed out, the ball barely got off the ground due to the fact that his hands are much too forward at impact, which decreases his dynamic loft too much, and this swing action may not be a functional swing action that a pro golfer could use competitively. When re-evaluating the video, the cadence of JE's pivot motion looks abnormal - being unnaturally too slow between P4 => P5.5 and then speeding up unnaturally between P5.5 => impact (and beyond impact). Ben Hogan definitely did not swing in that manner. JE may claim that he needs to have that unnatural pivot motion (slow startup=> faster later) in order to perform his "holding shaft flex" action through impact, but that may result in poor ball contact and/or a very short driving distance. To prove that this recent video-demonstrated driver swing action is really practical, JE really needs to hit a number of driver shots using a Trackman device, which can measure his clubhead speed at impact, ball speed at take-off + ball carry distance, and also his ball flight trajectory. If John refuses to be measured on GEARS, it could be very informative. He has a very defensive/obfuscating manner of debating issues in the ABS forum that makes me very suspicious of his intentions. Jeff.
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Post by dubiousgolfer on Sept 11, 2022 8:32:12 GMT -5
Dr Mann
Does JE shallow his club shaft with respect to his lead arm swing plane? I am assuming he isn't and that the shaft plane is on his lead arm swing plane.
I'm wondering whether he is inadvertently replicating SIM3 swing in SMK's research article "Club position relative to the golfer’s swing plane meaningfully affects swing dynamics".
This is where the golf swing model SIM3 was set up as per below:
"Simulation 3 (Sim3) was considered the reference condition, as the downswing swing was initiated with the shaft perfectly within the golfer’s swing plane and the optimization was conducted with all the torque generators available to supply energy to the system"
In SIM3 there was an active forearm rotational torque generator switched on which increased clubhead speed by 22% compared to the SIM1 swing (where the downswing started with the club shaft below the lead arm swing plane and forearm torque generator switched off).
Could JE be inadvertently using the above optimisation kinetics for SIM3 (ie. an active PA#3 action to increase clubhead speed as well as clubface squaring) but misinterpreting the physics using 'feel' to make sense of his own swing biomechanics (ie. making wrong assumptions about lagging shaft flex and accelerating torso pivot)?
DG
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Post by imperfectgolfer on Sept 11, 2022 10:13:49 GMT -5
Dr Mann Does JE shallow his club shaft with respect to his lead arm swing plane? I am assuming he isn't and that the shaft plane is on his lead arm swing plane. I'm wondering whether he is inadvertently replicating SIM3 swing in SMK's research article "Club position relative to the golfer’s swing plane meaningfully affects swing dynamics". This is where the golf swing model SIM3 was set up as per below: "Simulation 3 (Sim3) was considered the reference condition, as the downswing swing was initiated with the shaft perfectly within the golfer’s swing plane and the optimization was conducted with all the torque generators available to supply energy to the system" In SIM3 there was an active forearm rotational torque generator switched on which increased clubhead speed by 22% compared to the SIM1 swing (where the downswing started with the club shaft below the lead arm swing plane and forearm torque generator switched off). Could JE be inadvertently using the above optimisation kinetics for SIM3 (ie. an active PA#3 action to increase clubhead speed as well as clubface squaring) but misinterpreting the physics using 'feel' to make sense of his own swing biomechanics (ie. making wrong assumptions about lagging shaft flex and accelerating torso pivot)? DG John shallows his clubshaft to the hand plane by P6 and it remains on the hand plane between P6 => P7. That means that he has a larger accumulator #3 angle at impact. However, I don't believe that if a golfer has his clubshaft on the shallower hand plane between P6 => P7 that it can increase clubhead speed. It will, however, affect the pattern of overlap between the release of PA#2 => PA#3 so that a greater amount of lead forearm supination happens earlier between P6 => P6.5 while PA#2 is primarily being released. I don't believe that swinging the clubshaft on the hand plane automatically produces a "holding shaft flex" pattern and that requires a different swing technique with respect to the forces/torques being applied at the level of the club handle between P6 => P7 (irrespective of the steepness of the functional swingplane between P6 => P7). Jeff.
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Post by dubiousgolfer on Sept 12, 2022 11:02:35 GMT -5
JE barred me from the ABS forum for 'disrespectful posts' but obviously didn't bar all the other ABS posters who continually posted immature personal attacks on anyone who questioned their unproven beliefs. I think JE and Bradley Hughes are creating their own personal physics and here is a particular ludicrous example: "As far as the shaft flex debate… the reason you don’t see it… is because CF removes most of the visual backward curve in the shaft as velocities increase to 100 mph or greater. There is tremendous force acting downward or stretching the shaft longitudinally. Because the shaft is made of steel, it doesn’t stretch much, but the resistance pulls out the curve in the shaft into a straight line so you can’t see it. But that does not mean that the shaft is void of kinetic energy from the “holding shaft flex”… it is there. It’s like electricity Jeff, you can’t see “the energy”… but when you touch a hot wire, you get shocked or burned." He immediately deleted my post that showed this image of a CF force applied to the COM of a 'ruler/bolt' unit held in a hinged joint. This replicated what would happen to a golf driver shaft where the COM (the bolt in this case) is positioned behind the shaft. When a force is acted as shown, the COM/bolt moves in such a way that it aligns itself with the force and bends forward. One can clearly see that there is forward bend of the ruler and this is what happens to the driver shaft in a real golf swing as it approaches impact. In fact, the forward bend in a real golf swing is more than can be accounted for by this phenomenon and any 'extra' forward bend can be explained by the net negative torque applied by the hands on the grip. DG PS . In a real golf swing there is no green arrow CF force as shown in the above image. For example, if there were only a red arrow force (same magnitude as the green arrow) acting at the 'grip' end of the ruler (ie. no green arrow force), the COM of the ruler would still forward bend the same as in the above image and align itself with the red arrow force.
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Post by imperfectgolfer on Sept 12, 2022 15:05:48 GMT -5
John also removed the following post that I posted to the ABS forum and I have also been barred from the ABS forum. ---------------------------------------------------------------------------------------------------
John, You wrote-: " To hold shaft flex, you MUST NOT start the downswing quick or you will NEVER be able to keep pressure in the shaft. This IS THE PROBLEM with lightweight modern drivers. I don’t play these clubs for this reason. I have ZERO interest in losing pressure on the shaft tangentially through the strike." I can readily understand that point. However, I still want to understand why you do not manifest that "holding shaft flex" swing pattern in your "real life" golf swing actions. You performed many golf swing actions for the BeBetterGolf videos where you hit balls off your deck or in your backyard. And in those videos, there is no evidence that your pivot motion started slowly in your early downswing and there is no evidence that you were "holding shaft flex" during the late downswing and early followthrough. Here is an example from one of those full golf swing actions. Note that your peripheral clubshaft is bent back in image 1. That shows that you were already applying a lot of force/torque at the level of the club handle in the EARLY downswing and that you were "holding shaft flex", and that you were not "saving it for later". Image 2 shows that the peripheral clubshaft is bent backwards thereby showing that were "holding shaft flex". In images 3 and 4 the peripheral clubshaft is bent forward, which means that you were not "holding shaft flex". Image 5 shows that the clubshaft has bypassed your lead arm (from an angular rotational perspective) during your early followthrough, so you cannot possibly be "holding shaft flex". In other words, there is no evidence that you were "holding shaft flex" in your late downswing or early followthrough in that "real life" golf swing action. You performed a large number of full golf swing actions using either a driver or a 1-iron in those BeBetterGolf videos and there is no evidence that you were "holding shaft flex" in your later downswing or early followthrough in any of those many full golf swing actions. Why? Why do you only manifest a "holding shaft flex" pattern in your later downswing/early followthrough in your **special demonstration** videos (like the one that you featured in your last post)? Why does it not manifest in every full golf swing action that you performed for the BeBetterGolf video series where you were demonstrating the ABS-hitting technique? Jeff. -------------------------------------------------------------------------------------------- I personally think that John's "holding shaft flex" technique is an excellent technique for chipping and short iron shots under 100 yards. However, it is not practical for a driver or long iron swing because the PA#2 release phenomenon causes the peripheral clubshaft to travel faster than the club handle end after P6. If an ABS hitter tries to avoid an efficient PA#2 release phenomenon by starting the downswing slowly and then ramping up the speed of the pivot motion/arms after P6 it will potentially result in a considerable decrease in the maximum clubhead speed at impact. The ABS-groupies are like immature adolescents and they are incapable of indulging in a rational back-and-forth debate.
Consider this image. I guess that all the ABS-groupies must be Republicans!
Jeff.
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Post by imperfectgolfer on Sept 18, 2022 20:07:49 GMT -5
I strongly suspect that the golfer is Brendon Devore of BeBetterGolf, who was being instructed by John Erickson in the ABS-hitting technique. However, he is not "holding shaft flex" in the later downswing and early followthrough. Note that the animated gif's first image is at the ~P5.5 position and the peripheral clubshaft is bent backwards, which implies that he was "holding shaft flex" in his early downswing. However, between P5.5 => P7, and between P7 => P7.4, the peripheral clubshaft is bent forward, which means that he cannot be "holding shaft flex" during his late downswing and early followthrough. Although he is not really using the ABS-hitting technique of "holding shaft flex" in this particular golf swing action, it is still an excellent golf swing action where he is using a DH-hand release action through impact. Note how well he is rotating his pelvis/upper torso through impact and note how he is also ensuring that the angular velocity of his lead arm motion between P7 => P7.4 matches the angular velocity of the clubshaft so that the clubshaft never bypasses his lead arm (from an angular rotational perspective) between P7 => P7.4. Also note how he gets his trail shoulder moving well downplane through impact and that allows him to avoid a "running-out-of-trail arm" scenario so that he can still maintain a slightly bent trail wrist to P7.4.
This particular golf swing action is how I think that Brendon should routinely swing - using a TGM swinger's action and a DH-hand release action through impact. Although he is not using the ABS-hitting technique of "holding shaft flex" in the late downswing and early followthrough, the conceptual "idea" of performing the ABS-hitting technique has significantly improved his TGM swinger's action. Jeff.
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Post by playing18 on Sept 18, 2022 20:46:08 GMT -5
Jeff, his peripheral club shaft is clearly bending forward as you describe. What catches my eye is the significant weight pressure Brendon exerts through his lead foot from p5.5 to impact that makes his excellent pelvic rotation, lead shoulder motion, and drive hold release possible. Perhaps Brendon has enhanced this by doing Kwon’s stepping drills.
Jim (formerly utahgolfer)
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