Hmmm, lots of points to answer...
Dariusz-
I thank you for your honesty and understand your position.
At your service. Thanks for a well-spirited discussion to you and Virtuoso. Being honest should always be a basic virtue for a scientist.
Is it just me or does it seem like there are two seperate arguments regarding rate of closure? It seems as if the first argument is how much, if any, closure accurs during the impact interval and what effects it may or may not have on ballflight. The second argument is regarding the timing of the squarness of the clubface at impact. This argument hinges on the belief that a player with a clubface that is squarer longer has less timing involved to return a clubface square consistently than a player that has a lot of rotation nearing impact.
I think enough evidence exists to refute the first argument; the ball and club simply aren't in contact long enough for clubface closure during impact to influence ballflight. Regarding the second argument, it would certainly seem as if a clubface that is "more square" longer would be easier to return to square on a consistent basis. It seems as if it would be easier to consistently rotate the clubface from 10 degrees open to square that it would be to rotate the clubface from 50 degrees open to square. When we putt we try to hold the clubface reasonable square so we can consistently hit the ball where we aim...I think it would be difficult to roll the wrists and forarms rapidly open to square and start the ball on line often enough to putt well. I would assume the same would apply to the full swing.
I don't know the answers to these questions, but it is a good discussion and I appreciate everyone doing the research to try to find the answers.
Very good post summing perfectly the meanders of all RoC discussions. I really do not know, BTW, why must it take so much time to revert constantly to a completely insignificant RoC between impact and separation.
People talk about rate of closure but don't really elaborate on it.From what point to what point is ROC more important-during the impact interval or from last parallel to impact?Are they mutually exclusive?Would a high ROC from last parallel to impact result in a higher or lower ROC during the impact interval?
Players like Hogan and Sergio would "appear" on video to have a high ROC from last parallel to impact as they have a very laid off shaft deep into their downswing and then tumble like crazy to square it up at impact.No way Jose I can do that and probably most players.
Good question. I would say this -- if Cotton as the first guy ever distinguished three release types basing on vertical and horizontal change of clubface angle he should have thought where it happens. While we can exclude very srtict impact zone (between contact and separation) for reasons already stated several times with the main one that there is no visible difference not only for bare eyes (Cotton) but also for precise instruments (nowadays) -- we need to widen the arc sector.
How much ? I would say at least to the extent the most stable RoC player can maintain perpendicularity of his clubhead (3-D perpendicularity, of course) to the arc before and after impact.
Maybe rate of left/right wrist closure is what some people would like to measure instead?
Nope. Clubhead RoC. If we know what players have extremely low clubhead RoC we can start to analyze why it happens. It will probably occur that a grip type is one of the factors, but I am almost certain it will not be a primary issue.
Somebody stop the fight, this thing's over.
What's over ?
Basically, the hips reach max speed in most every good player, when the hips return to square.
Yes. The data of the Polish National Junior Team confirms it. One should add though that good players must have tremendously accelerate before so that so early decceleration is possible. Lastly, that in case of best players rotation lasts through impact which, coincidentally, is a very important thing IMO in distinguishing release types.
Dariusz,
What I think you fail to see is how the "weakness" of the grips employed by Donald and Hogan effectuate the same seen movement ("the flip") in both swings. Forget about "crossover" or whatever. Let's try and be more precise. I'm just as guilty of being vague.
So here goes. At address, both players have their left arm "preset" in a very supinated position. The left palm is facing more skyward, towards the face than with most players. The grip runs in the base of the left hand. The right hand almost seems to fall into the left as in a clap. The feeling is that the right hand is right on top of that darn shaft. Once the grip is in this position, wrist action is "preset" to occur mostly in what could be called the ulnar deviation plane/vertical cocking plane.
But it's not. And that's the secret to their grips.
Forget what anatomical plane you think the swings are on. Let's call it a vertical cocking plane. Not the ulnar deviation/cross-over plane or the flexion/extension/slow & stable RoC plane.
In what plane is the motion occurring?
Why is it a heresy to think that players who you don't deify may have used similar biomechanics to the Great Ben Hogan? Maybe that's what you need to learn if you're going to really be a Hogan fan. It wasn't the biomechanics that separated him from his peers. It was the sheer tenacity. If you love him as much as you do you really should get to know him.
Lia, as I said earlier, we cannot go from the arse back. If a scientist is going to reveal finally theclubhead RoC mystery, he/she must start
from choosing player models while measuring clubhead, not damn lead wrist rotation. If you observe Hogan (with bare eyes in slo-mo) you can see (with a dose of probability of mistake because of lack of precise tools) that after he returns his clubface square-to-the-arc he maintains it perfectly in a relatively wide impact zone. Same with Furyk, etc.
As regards your term "flip" -- it is not the same movement. Donald rotates his clubhead in much bigger rate than Hogan. Hogan maintains horizontal edge of the clubface perpendicular to the arc in a much bigger arc sector. The lead wrist dorsal flexion gives an illusion of rotation, but it is only an illusion. It's enough to observe how clubhead looks. That's why I say measure clubhead, not any wrist movements.
Cheers
