Science Schmience - Different Strokes?

I'd like to post an occasional thread about pool "science" for those who are interested. I know that there are some very knowledgeable, experienced and highly skilled players here who have no interest in such "egghead" stuff, and it may even cause some friendly(!) controversy, but I believe it's a topic that will find some interest here and is largely missing so far.

So here goes the first Science Schmience topic:

Different Strokes?

Many excellent players advocate different strokes for different kinds of shots, even different strokes for follow and draw. But "science" says the stroke is a simple thing and the only things that matter to the shot are (1) where the CB is struck, (2) from what angle, and (3) how hard.

Science also says that the length of follow through, whether the stroke is accelerating, decelerating or coasting and even whether or not the stroke is straight don't have any direct bearing on the shot's outcome, and only affect the player's ability to reliably deliver the cue to the desired CB contact point at the desired stroke angle and speed. This means that any shot a master player can do can also be done by any simple stroke robot - and, most importantly to us humans, that we don't need to learn lots of stroke "secrets"; we just need to learn to deliver the cue accurately (easier said than done!).

I look forward to your comments (I think).

pj <- asbestos underwear on
chgo

[COLOR=blue said:

Science also says that the length of follow through, whether the stroke is accelerating, decelerating or coasting and even whether or not the stroke is straight don't have any direct bearing on the shot's outcome, and only affect the player's ability to reliably deliver the cue to the desired CB contact point at the desired stroke angle and speed. This means that any shot a master player can do can also be done by any simple stroke robot - and, most importantly to us humans, that we don't need to learn lots of stroke "secrets"; we just need to learn to deliver the cue accurately (easier said than done!).[/COLOR]

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The portion in red effectively negates the subsequent statement and the entire argument that different strokes have no effect. To put it simply, if a different stroke aids or enables a person to strike the cue ball in the desired manner more consistently or accurately it has plenty of effect.

Note: this is especially the case with follow through and applies in any sport that involves propelling an object. Try stopping your golf swing at the moment of impact without affecting the outcome.

cary

Originally Posted by Patrick Johnson
Science also says that the length of follow through, whether the stroke is accelerating, decelerating or coasting and even whether or not the stroke is straight don't have any direct bearing on the shot's outcome, and only affect the player's ability to reliably deliver the cue to the desired CB contact point at the desired stroke angle and speed. This means that any shot a master player can do can also be done by any simple stroke robot - and, most importantly to us humans, that we don't need to learn lots of stroke "secrets"; we just need to learn to deliver the cue accurately (easier said than done!).

Click to expand...

The portion in red effectively negates the subsequent statement and the entire argument that different strokes have no effect.

Click to expand...

Science doesn't say that different strokes have no effect; it says they have no direct effect (as I say above) - in other words, if you deliver your cue tip to the CB accurately, then it doesn't matter how you did it.

To put it simply, if a different stroke aids or enables a person to strike the cue ball in the desired manner more consistently or accurately it has plenty of effect.

Click to expand...

This is absolutely correct - how you do it can have a great effect on whether you can do it, especially whether you can do it every time.

Knowing this can help us focus on what's really important - developing a reliable, repeatable, accurate stroke, using principles and methods that are effective for that.

pj
chgo

mr3cushion said:

No Comment!

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LOL. I know you're a skeptic, Bill, and I respect that. I hope you'll read some of this and find out that we don't really disagree so much after all. My guess is our differences are more semantics than substance.

pj
chgo

It's hard to disagree with all that without appearing to be a flat-earther, but there is the question of empirical (not theoretical) evidence to support the conclusions. Maybe a stroke-bot can be built that executes a perfectly repeatable tip delivery to an experimental cb, but whether a human can be found who can do the same is doubtful. I think you'd need both in order to do the experiment.

So, that's my analysis and I'm sticking to it...unless Patrick whips out some awfully convincing empirical data to change my mind!

Skin

Skin said:

It's hard to disagree with all that without appearing to be a flat-earther, but there is the question of empirical (not theoretical) evidence to support the conclusions. Maybe a stroke-bot can be built that executes a perfectly repeatable tip delivery to an experimental cb, but whether a human can be found who can do the same is doubtful. I think you'd need both in order to do the experiment.

So, that's my analysis and I'm sticking to it...unless Patrick whips out some awfully convincing empirical data to change my mind!

Skin

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I think you'd only need to have a game of "horse" between the player(s) and the robot; a player executes a shot and then the robot does the same - repeat for different shots that supposedly require different strokes. This hasn't been done (that I know of), so this kind of empirical data hasn't yet been collected.

But there is some empirical data that guides good theory - for instance, it has been shown that tip/cueball contact lasts for only 1/1000 of a second or so, too short for stroke factors other than accuracy, angle and speed to matter - and we can't significantly change that.

Is there any good theoretical basis for the notion that different kinds of strokes are needed if the cue can be accurately delivered with one kind?

pj
chgo

Skin said:

It's hard to disagree with all that without appearing to be a flat-earther, but there is the question of empirical (not theoretical) evidence to support the conclusions. Maybe a stroke-bot can be built that executes a perfectly repeatable tip delivery to an experimental cb, but whether a human can be found who can do the same is doubtful. I think you'd need both in order to do the experiment.

So, that's my analysis and I'm sticking to it...unless Patrick whips out some awfully convincing empirical data to change my mind!

Skin

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Flat Earther:lol...Never heard that.. like it
....Sorry!...Back to Science

Different Strokes for Different Folks.
Rod.
P.S. Where's Sunny when we need her.

Patrick

Putting "science says" in front of a statement doesn't make it scientific. Also having a theoretical basis for a statement doesn't mean that it is scientifically supported.

Scientific ideas are ultimately rooted in reality. That means the model has to approximate reality and the subsequent theory and it's predictions have to be supported empirically. (This is roughly what is called the scientific method.)

I think your premise (hypothesis) is that you can exactly determine (predict) the motion of the cueball solely from the momentum of the cue...independently of the rate of change of momentum (i.e. acceleration) or any higher derivatives of momentum with respect to time.

I don't have sufficient systematic evidence to show you that your premise is false...so I won't say that it is incorrect. However in my personal experience i think the type of stroke does change the result of the cue ball motion. The rate of change of momentum does matter.

In any case what I really wanted to say is that while you use language that sounds scientific..I don't think what you say is actually scientifically supported.

Respectfully

Lou

Patrick Johnson said:

I'd like to post an occasional thread about pool "science" for those who are interested. I know that there are some very knowledgeable, experienced and highly skilled players here who have no interest in such "egghead" stuff, and it may even cause some friendly(!) controversy, but I believe it's a topic that will find some interest here and is largely missing so far.

So here goes the first Science Schmience topic:

Different Strokes?

Many excellent players advocate different strokes for different kinds of shots, even different strokes for follow and draw. But "science" says the stroke is a simple thing and the only things that matter to the shot are (1) where the CB is struck, (2) from what angle, and (3) how hard.

Science also says that the length of follow through, whether the stroke is accelerating, decelerating or coasting and even whether or not the stroke is straight don't have any direct bearing on the shot's outcome, and only affect the player's ability to reliably deliver the cue to the desired CB contact point at the desired stroke angle and speed. This means that any shot a master player can do can also be done by any simple stroke robot - and, most importantly to us humans, that we don't need to learn lots of stroke "secrets"; we just need to learn to deliver the cue accurately (easier said than done!).

I look forward to your comments (I think).

pj <- asbestos underwear on
chgo

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...when I was 9 years old...my Parents bought me a....chemistry set....within a few days I managed to burn down the shed that my Father set up for Me..... since then I haven't been allowed to play with Science.......

.....so, although your thread seems very interesting....I will have to continue relying on....Myth and Magic....or maybe the UPS...to deliver the rock to it's designated contact point.....

....PS....the Earth is flat...if it wasn't We'd all fall off....

pvclou said:

Patrick

Putting "science says" in front of a statement doesn't make it scientific. Also having a theoretical basis for a statement doesn't mean that it is scientifically supported.

Scientific ideas are ultimately rooted in reality. That means the model has to approximate reality and the subsequent theory and it's predictions have to be supported empirically. (This is roughly what is called the scientific method.)

I think your premise (hypothesis) is that you can exactly determine (predict) the motion of the cueball solely from the momentum of the cue...independently of the rate of change of momentum (i.e. acceleration) or any higher derivatives of momentum with respect to time.

I don't have sufficient systematic evidence to show you that your premise is false...so I won't say that it is incorrect. However in my personal experience i think the type of stroke does change the result of the cue ball motion. The rate of change of momentum does matter.

In any case what I really wanted to say is that while you use language that sounds scientific..I don't think what you say is actually scientifically supported.

Respectfully

Lou

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UH; What He said!

androd said:

Different Strokes for Different Folks.

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Yup - whatever works best for you is clearly the thing to do.

My question is: are the different "kinds" of strokes really just different paths to the same simple spot-angle-speed for the shot?

And, of course: so what?

pj
chgo

Patrick Johnson said:

I think you'd only need to have a game of "horse" between the player(s) and the robot; a player executes a shot and then the robot does the same - repeat for different shots that supposedly require different strokes. This hasn't been done (that I know of), so this kind of empirical data hasn't yet been collected.

But there is some empirical data that guides good theory - for instance, it has been shown that tip/cueball contact lasts for only 1/1000 of a second or so, too short for stroke factors other than accuracy, angle and speed to matter - and we can't significantly change that.

Is there any good theoretical basis for the notion that different kinds of strokes are needed if the cue can be accurately delivered with one kind?

pj
chgo

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I'm not going to argue because to my view, what works is whatever works for a given player. There have been many great great players that did not necessarily understand the "science" but they sure could accomplish near miracles at the table. and often with a consistency that I can only fantasize about!! I.e., it is tough to argue with success.

However, one thing you mention does get my attention, and that is the "or so" that you tacked on to the 1/1000 of a second. I mean, just because a thousandth of a second is not very much time does not mean it is not enough time to matter, does it?? What it means to me is that it is such a short amount of time, then even a very slight difference in contact could well matter quite a bit, couldn't it?

I am pretty sure I get a different amount of "squirt" if I jab at the cue ball than I do if I stroke through the cue ball, and I can only assume my speed of stroke must be similar based on the resulting distance the object ball and cue ball travel, so I cannot ascribe the difference to speed. The extra squirt certainly changes my accuracy, but which is it -- the cause, or the effect, lol? Likewise, if I shoot with a stiff grip and wrist I don't get nearly the action on the cue ball that I seem to if I loosen my grip and flex my wrist -- again, even if the object ball travels about the same distance.

Are you saying the difference is only in my contact point or speed of stroke? It seems to me there is another difference that does have to do with the kind of stroke going on.

I forgot to mention, soft vs hard tips & different shafts. Wouldn't a softer tip linger a tiny fraction longer on the cue ball than a hard tip? Also, shafts with higher deflection, doesn't the cue tip have to linger a fraction longer on the cue ball than a shaft with lower deflection? I mean, these would be tiny fractions, but like you said, the moment of contact is very short anyway, so what's another ten thousands of a second "or so" -- well, just maybe that extra 10% is enough to make a little difference...

I am an engineer and can subscribe to a scientific treatment of the topic. What I find hard to accept in your statement is discounting the effect of acceleration. I have often pondered what is this thing we call "stroke", and every time (without scientific backing), I conclude that it has to do with the acceleration of the tip. Is there evidence that supports acceleration not affecting cue ball reaction?

If the tip-ball contact of 1ms is changed by +/-10%, wouldn't that change how the cue ball reacts? It's a game of inches ...

(I like the topic and just want to add my thoughts).

tree

Patrick Johnson said:

I'd like to post an occasional thread about pool "science" for those who are interested. I know that there are some very knowledgeable, experienced and highly skilled players here who have no interest in such "egghead" stuff, and it may even cause some friendly(!) controversy, but I believe it's a topic that will find some interest here and is largely missing so far.

So here goes the first Science Schmience topic:

Different Strokes?

Many excellent players advocate different strokes for different kinds of shots, even different strokes for follow and draw. But "science" says the stroke is a simple thing and the only things that matter to the shot are (1) where the CB is struck, (2) from what angle, and (3) how hard.

Science also says that the length of follow through, whether the stroke is accelerating, decelerating or coasting and even whether or not the stroke is straight don't have any direct bearing on the shot's outcome, and only affect the player's ability to reliably deliver the cue to the desired CB contact point at the desired stroke angle and speed. This means that any shot a master player can do can also be done by any simple stroke robot - and, most importantly to us humans, that we don't need to learn lots of stroke "secrets"; we just need to learn to deliver the cue accurately (easier said than done!).

I look forward to your comments (I think).

pj <- asbestos underwear on
chgo

Click to expand...

treeMan said:

I am an engineer and can subscribe to a scientific treatment of the topic. What I find hard to accept in your statement is discounting the effect of acceleration. I have often pondered what is this thing we call "stroke", and every time (without scientific backing), I conclude that it has to do with the acceleration of the tip. Is there evidence that supports acceleration not affecting cue ball reaction?

If the tip-ball contact of 1ms is changed by +/-10%, wouldn't that change how the cue ball reacts? It's a game of inches (I like the topic and just want to add my thoughts).

tree

Click to expand...

... In 3C, "It's a game of millimeters!"

Patrick Johnson said:

Yup - whatever works best for you is clearly the thing to do.

My question is: are the different "kinds" of strokes really just different paths to the same simple spot-angle-speed for the shot?

And, of course: so what?

pj
chgo

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bingo......
patrick im a science guy at heart.....o?)
and to me pool is applied physics
but since we are not computers or robots
we (humans) need images (strokes) /call it what you want
to hook to for repeatable results
jmho
no person who looks at things OBJECTIVELY
could deny that it really is
WHERE YOU STRIKE THE CUEBALL
AT WHAT ANGLE
AT WHAT SPEED
determines what happens
NOW how do you learn to hit a shot the way to make it
you associate it with this "STROKE" which is the message which sends the message to you brain to hit it with the correct speed /tip placemant/angle of cue
to make the shot AND GET THE CUE BALL TO GO WHERE YOU WANT
,,,,,
ICBW

lll said:

bingo......
patrick im a science guy at heart.....o?)
and to me pool is applied physics
but since we are not computers or robots
we (humans) need images (strokes) /call it what you want
to hook to for repeatable results
jmho
no person who looks at things OBJECTIVELY
could deny that it really is
WHERE YOU STRIKE THE CUEBALL
AT WHAT ANGLE
AT WHAT SPEED
determines what happens
NOW how do you learn to hit a shot the way to make it
you associate it with this "STROKE" which is the message which sends the message to you brain to hit it with the correct speed /tip placemant/angle of cue
to make the shot AND GET THE CUE BALL TO GO WHERE YOU WANT
,,,,,
ICBW

Click to expand...

Ed Zackery.
Rod.

Patrick Johnson said:

I'd like to post an occasional thread about pool "science" for those who are interested. I know that there are some very knowledgeable, experienced and highly skilled players here who have no interest in such "egghead" stuff, and it may even cause some friendly(!) controversy, but I believe it's a topic that will find some interest here and is largely missing so far.

So here goes the first Science Schmience topic:

Different Strokes?

Many excellent players advocate different strokes for different kinds of shots, even different strokes for follow and draw. But "science" says the stroke is a simple thing and the only things that matter to the shot are (1) where the CB is struck, (2) from what angle, and (3) how hard.

Science also says that the length of follow through, whether the stroke is accelerating, decelerating or coasting and even whether or not the stroke is straight don't have any direct bearing on the shot's outcome, and only affect the player's ability to reliably deliver the cue to the desired CB contact point at the desired stroke angle and speed. This means that any shot a master player can do can also be done by any simple stroke robot - and, most importantly to us humans, that we don't need to learn lots of stroke "secrets"; we just need to learn to deliver the cue accurately (easier said than done!).

I look forward to your comments (I think).

pj <- asbestos underwear on
chgo

Click to expand...

I agree. I think it is also true -- and this is what leads to a lot of confusion -- that some players may find -- or simply believe -- that different strokes on different kinds of shots make it easier or more comfortable for them to deliver the tip to right part of the cb from the right angle with the right amount of force. It may even be true that this is the case for everyone, but the bottom line is that angle, force and location matter, but what happens before and after that does not.

One example: "Follow through" helps only because it creates a picture in the shooter's mind that facilitates ideal contact, but what happens after that 1000th of a second is irrelevant.

BTW, the best argument detractors have, IMO, is that "science says" (doesn't it?) that a baseball can't be thrown hard enough or spun enough to curve more than minutely.