C.J.'s touch of inside

skipbales

AzB Silver Member
Silver Member
I am on vacation, but when I get back, I will do a careful analysis and post something.

Regards,
Dave

Hey Dr. Dave, thanks for participating. I have a great deal of respect for your teaching. I have the Veps Pool Shots series and have watched then all many times. I feel you have the best technical presentation of what actually happens in pool of any of the videos I have watched and I have watched a LOT of them. :wink:
 

dr_dave

Instructional Author
Gold Member
Silver Member
Inside english offers many advantages, as listed on the inside english resource page.

However, when one uses english, in addition to adjusting for throw, one must also adjust for CB deflection resulting from squirt and swerve (see squirt and swerve effects). These effects vary with shot shot speed and distance, type and amount of spin, cue elevation, and conditions, so using inside english when it is not required for CB control is probably not a good approach for most people.
While all of this is true, we are faced with an assertion in this thread that has been repeated elsewhere that a miss by distance +/- x from a center ball hit equals a miss by +/- x on a hit using inside english. Support for that was that squirt is equal in either case which is true. But that argument failed to take throw into account. If one factor, whether it be squirt, swerve or throw is not equal in both cases, then the assertion is untrue. That was the main point of my discussion.

Do you disagree that even if swerve and squirt are constant in each case, the fact that throw differs disproves the assertion?
I said I would do a "careful analysis" after my vacation (I'm back), but I honestly don't think it is worth the effort (which would be significant and might involve many assumptions). Regardless, I think the "big picture" concepts are clear:

- for a given tip placement error (left/right of the desired tip contact point), the resulting squirt error is the same for an off-center hit (e.g., with inside) as compared to a center-ball hit.
- for small cut angles, the amount of throw will be larger for inside english shots, and this will cause errors if not compensated accurately.
- for larger cut angle shots, the amount of throw will be larger for center-ball shots, and this will cause errors if not compensated accurately.
- in general, throw is more consistent for small changes in tip position for inside english vs. center-ball shots; but if the amount of throw is not judged properly, there will still be errors.

Squirt, swerve, and throw effects are not simple, and they vary a lot with shot speed, shot distance, cue elevation, type and amount of spin, and conditions. For those interested in learning more, lots of info/videos/articles on this topic can be found here:

squirt, swerve, and throw effects resource page

Regards,
Dave
 
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Patrick Johnson

Fish of the Day
Silver Member
Friend, I don't see how you ever make a ball if you're going through all those mental gymnastics when playing the game.
He isn't; his subconscious is. So is yours. I'm pretty sure his subconscious gymnastics only really differ from yours in the way you think of them away from the table.

pj
chgo
 

JoeyInCali

Maker of Joey Bautista Cues
Silver Member
Friend, I don't see how you ever make a ball if you're going through all those mental gymnastics when playing the game. Honest I don't. (and I know you can play, I've seen you)
All someone has to do is to learn and use the CTE aiming system and the issues of throw, squirt, and all that other stuff are taken care of automatically....making the game enjoyable instead of a struggle.
To my way of thinking, dealing with the pressure of everyone pulling against you, noise, the prize money, and the other matters of combat are tough enough in themselves without adding scientific mental work to the pot.
I guess, in my case, ignorance is bliss.....................but the balls don't know that.
:thumbup:
Please.
It doesn't .
That's why some use low deflection shafts.

Even Cookie admits you have to use judgment on throws and squirts .
 

JoeyInCali

Maker of Joey Bautista Cues
Silver Member
Keep trying Joey.....you'll learn how to shoot good pool some day.
:thumbup:

So, your CTE takes care of your PSR, takes care of the throw and deflection.



And you think the people who call it snake oil are wrong?
 

dr_dave

Instructional Author
Gold Member
Silver Member
I said I would do a "careful analysis" after my vacation (I'm back), but I honestly don't think it is worth the effort (which would be significant and might involve many assumptions). Regardless, I think the "big picture" concepts are clear:

- for a given tip placement error (left/right of the desired tip contact point), the resulting squirt error is the same for an off-center hit (e.g., with inside) as compared to a center-ball hit.
- for small cut angles, the amount of throw will be larger for inside english shots, and this will cause errors if not compensated accurately.
- for larger cut angle shots, the amount of throw will be larger for center-ball shots, and this will cause errors if not compensated accurately.
- in general, throw is more consistent for small changes in tip position for inside english vs. center-ball shots; but if the amount of throw is not judged properly, there will still be errors.

Squirt, swerve, and throw effects are not simple, and they vary a lot with shot speed, shot distance, cue elevation, type and amount of spin, and conditions. For those interested in learning more, lots of info/videos/articles on this topic can be found here:

squirt, swerve, and throw effects resource page
Friend, I don't see how you ever make a ball if you're going through all those mental gymnastics when playing the game. Honest I don't. (and I know you can play, I've seen you)
All someone has to do is to learn and use the CTE aiming system and the issues of throw, squirt, and all that other stuff are taken care of automatically....making the game enjoyable instead of a struggle.
To my way of thinking, dealing with the pressure of everyone pulling against you, noise, the prize money, and the other matters of combat are tough enough in themselves without adding scientific mental work to the pot.
I guess, in my case, ignorance is bliss.....................but the balls don't know that.
:thumbup:
I never think about physics and math analysis while I am playing, but my understanding of the effects does help me when I plan and aim certain types of shots. Regardless, I don't think about any of this stuff on most shots. And even when I do adjust my aim, I still don't think in my stance or when I shoot.

Regards,
Dave
 
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Patrick Johnson

Fish of the Day
Silver Member
All someone has to do is to learn and use the CTE aiming system and the issues of throw, squirt, and all that other stuff are taken care of automatically / subconsciously....
I think these are the same thing in many players' minds.

pj
chgo
 
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JoeyInCali

Maker of Joey Bautista Cues
Silver Member
Well, Joey. I guess the bottom line is if you believe the CTE is snake oil....I'd suggest you definitely leave the CTE alone and have absolutely nothing to do with it.
The question remaining, from my perspective, is if you believe that as you say....why do you even give a flip about it from a public comment standpoint? Why not just ignore it and all of its followers...forget it exists and move on to something else??
Just leave us alone to flounder in our ignorance. Isn't that reasonable??
Goodbye Joey.

Or you can stop with the BS claims.
Go ahead prove me wrong.
Let's see you shoot inside spin spot shots .
Let me know where the cue ball ends after you pocket the ball.
Then we can make bets .
 

BilliardsAbout

BondFanEvents.com
Silver Member
IMHO,

1) It's quite difficult to run a rack using outside on every stroke (or at least, more than a "touch of" outside).

2) The closer a stroke is to the cb vertical axis, the fewer variables and hassle/squirt/deflection/throw (in general).

3) TOI is a tiny, almost imperceptible amount of inside "parallel" (both hands) to favor giving the player a shorter cb roll on all shots including MISHITS -- players who aim vertical axis and miss could be dealing with unwanted outside english -- players who MISHIT TOI tend to get more inside or center ball.

4) A pro is a player who rarely misses but for unexpected throw (from ball dirt) and etc. Some pros use TOI on some shots to give them added control.
 

skipbales

AzB Silver Member
Silver Member
He isn't; his subconscious is. So is yours. I'm pretty sure his subconscious gymnastics only really differ from yours in the way you think of them away from the table.

pj
chgo

Very true. It is one thing to understand EXACTLY how things work. A completely different thing to be able to do things. It is like driving a car vs. understanding mechanically how it all works.

I think you and I both like to do both. :smile:
 

bioactive

AzB Silver Member
Silver Member
I said I would do a "careful analysis" after my vacation (I'm back), but I honestly don't think it is worth the effort (which would be significant and might involve many assumptions). Regardless, I think the "big picture" concepts are clear:

- for a given tip placement error (left/right of the desired tip contact point), the resulting squirt error is the same for an off-center hit (e.g., with inside) as compared to a center-ball hit.
- for small cut angles, the amount of throw will be larger for inside english shots, and this will cause errors if not compensated accurately.
- for larger cut angle shots, the amount of throw will be larger for center-ball shots, and this will cause errors if not compensated accurately.
- in general, throw is more consistent for small changes in tip position for inside english vs. center-ball shots; but if the amount of throw is not judged properly, there will still be errors.

Squirt, swerve, and throw effects are not simple, and they vary a lot with shot speed, shot distance, cue elevation, type and amount of spin, and conditions. For those interested in learning more, lots of info/videos/articles on this topic can be found here:

squirt, swerve, and throw effects resource page

Regards,
Dave

Thanks for the reply but I had a specific original question. I understand if you don't want to take the time to address it but this response did not. Please consider this question in the context of TOI practice. The fundamentals are that swerve has been minimized by shooting sharply, the reference ghost ball line is towards and undercut position, squirt is carefully controlled and calibrated for the shooter. The comparison shot is a center ball hit to center pocket.

My original question:

Originally Posted by bioactive View Post
While all of this is true, we are faced with an assertion in this thread that has been repeated elsewhere that a miss by distance +/- x from a center ball hit equals a miss by +/- x on a hit using inside english. Support for that was that squirt is equal in either case which is true. But that argument failed to take throw into account. If one factor, whether it be squirt, swerve or throw is not equal in both cases, then the assertion is untrue. That was the main point of my discussion.
 
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bioactive

AzB Silver Member
Silver Member
My comment was only about how to produce maximum throw, not about its application to TOI, but...

Interesting observation about variance in throw with inside vs. outside - I'll have to spend some time with Dr. Dave's analysis before I can speak to that. But I don't recall throw being part of CJ's "reasoning" - as I recall he was focused entirely on using squirt to improve pocketing percentages. Throw has the opposite effect of squirt on aiming, so I wonder how that factors into your assessment of TOI.

You might be right about favoring inside for shots that don't need CB control, but in my experience that situation is rare even for game balls.

pj
chgo

While he does not say it in a concise, linear manner, the TOI approach as practiced by CJ (and taught differently over time) is to "shoot the same shot every time", by using a known, calibrated amount of squirt from an undercut line, striking from the inside, and a minimized magnitude of swerve, achieved with velocity, leaving throw as the main remaining substantial variable, the variability of which is reduced by the use of inside compared to outside.

Moreover, the nature of the inside he is using is different than anything I have seen described by Dr. Dave or anyone. Imac007 has tried to describe this but no-one has paid attention to it yet, or more likely not made the effort to dissect it. If properly applied, the TOI approach as Imac007 describes it is applying a vector through the cue ball that I had not seen described previously.

From Imac007 earlier in this thread:

"PJ, I understand your perspective because it used to be mine. Since then I have become highly aware that I created scenarios that didn’t match the facts. Let me explain using some research done by Dr. Dave.

From David G. Alciatore, PhD (“Dr. Dave”) ILLUSTRATED PRINCIPLES “Throw – Part VII: CIT/SIT combo” https://billiards.colostate.edu/bd_a...2007/feb07.pdf. Diagram 4

To put this in context, the idea is that every cut shot has some inherent amount of throw. Maximum throw occurs at about 30-35°, roughly a half ball shot, when slow stun is used. If however the ball has vertical rotation, follow or draw, and is shot with medium pace, the throw using inside side is consistent. Regardless of angle, medium paced, draw or follow show a consistent throw deviation was found across the cut angles tested. There was 1° of throw consistent across the entire range tested. A rolling ball is a rolling ball when it contacts the object ball and is treated as follow. The only other state is a sliding ball, stun. When a slow stun shot with maximum inside english is applied the throw amount is slightly higher resulting in 3-4° of throw across that same range of angles. A center soft stun shot has throw effects varying from near zero to as high as 5°. The point is that inside side offers the shooter a consistent single adjustment across all cut angles tested.

Another graph https://billiards.colostate.edu/bd_a...2006/dec06.pdf , looked at the effect of degrees of english from small to maximum at varying speeds. A straight shot was tested to check speed vs throw dynamics. One conclusion stood out when considering a small amount of english. "SIT is independent of speed (i.e., the throw is the same at all speeds) for small amounts of English."

Logic tells us that the small amount of english dynamic, especially inside english, should apply across all angles consistently, regardless of speed, even at cut angles. In fact, one of the other graphs https://billiards.colostate.edu/bd_a...007/sept07.pdf compares squirt dynamics for different speeds at different cue offsets. The smallest offset tested was .21". That amounts to 5.3mm of side. CJ defined his amount of inside as ⅛ tip. An eighth of a 12 mm tip is 1.5mm. The three offsets tested were .15" apart. That is about 3.8mm. Coincidentally the ⅛ tip CJ used just happens to be that much less than the smallest tested. While each of the tested offsets resulted in roughly a single degree less deflection as offset decreased, the trend is further confirmation that "SIT is independent of speed (i.e., the throw is the same at all speeds) for small amounts of English."

When CJ followed his process of shifting the butt then the tip slightly, he guaranteed a very small amount of inside. The sharpness of the angle to the inside forced him to temper the inside move on long shots. That in fact created a different offset. The research led to refinements to his system that address its problems and led to new understandings of determining true offsets. Consistent offset combined with the science of inside side allow players to significantly reduce the effects of throw. Complexity around adjusting for angle, speed and offset deflection all collapse into a single treatment for the majority of shots.

There is more, but the idea that all this is "beside the point" creates an avalanche of cognitive dissonance. I’m just sharing some of the things learned going down this path that changed my perspective. It’s rare that I now need to calculate adjustments for throw. "


He further has created a set of terms that are needed to describe the mechanics of what is happening under TOI. Think about the vector produced and you might get more meaning from this. When I "got it" it was like a diamond bullet to the forehead.
Take the time to understand the forces applied by TOI as alluded to by Imac and you too might have that experience.

From Imac007 earlier in this thread.

"These ideas are not an aiming system. The concept grafts onto whatever aiming system uses center ball. The work and graphs of Dr. Dave were invaluable. New ideas like convergence, inflection, and torque line give us new horizons to explore. These are physical concepts, not theories. CJ was a pioneer who made us think differently. He went down one path with his shift in thinking, but he opened up a new world of possibilities."

Follow the vector arrow into the rabbit hole.

Convergent English: Cueing towards the center of the cue ball but passing the center on the same side as the cue tip was placed. Creates a torque line near center cue ball that defines the magnitude of deflection and spin.

Diagram of Convergent English:

convergent%20diagram%20final-final_zps3drr23lv.jpg
 
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skipbales

AzB Silver Member
Silver Member
While he does not say it in a concise, linear manner, the TOI approach as practiced by CJ (and taught differently over time) is to "shoot the same shot every time",

CJ told me the last time I was there "maybe I should have called it a hair of inside". His explanation was that almost all professional players slightly favor either the inside or outside. I don't think he analyzed it as technically as you guys but there is certainly nothing wrong with doing that analysis.

As bioactive states his goal was a consistent shot. A little inside, no inside or a little more than intended vs. a little inside, dead center and a little outside. He preferred the consistency of his mis hits being from nothing to a little more than expected inside but never out side. In most cases the inside is reverse English not running English so it deadens things a little and he calls that "floating into position" vs. spinning. He was trying to perfect one type of shot and use it everywhere possible instead of have more options he wanted fewer and he wanted to be better at the smaller number of options. Sometimes inside is also running but it is always with the same angle shots so he is used to that extra speed in those cases.

In the same way he tries to avoid a lot of speed changes and hit a more constant speed on each shot, going more rails for position if necessary vs. slow rolling, etc. He called that "making the table fit his game" instead of the other way around.

To me it was all about consistency and trying to lessen variables. You guys have taken it to another level. You are right bioactive, he gave us new things to think about and to me that is all good.
 
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