double-the-distance aiming method (PIM: Pocket Intersection Method)

[dr_dave]

I'd like to hear from anyone in the world reading the thread who thinks CTE is geometrically incorrect - to prove why it is.

Dave,

If you are serious about this, we would first need to clearly define what "geometrically correct" means, as applied to an "aiming system." I'll take a stab so others can help expand or improve the definition:

geometrically correct aiming system: a method involving a clear and reproducible set of steps that, in theory, accurately locate the line (the required aiming line) passing exactly through the center of the ghost-ball target for any shot.
​

Vision, alignment, perception, judgment, feel, conscious or subconscious adjustments, stroke accuracy or consistency, etc. are not part of the test for "geometric consistency." Geometric consistency refers to the theory of the system, not the implementation of the system. As I and others have pointed out, some of the systems that are geometrically consistent in theory (e.g., bisect-pivot-and-shift aiming system and contact-point-to-contact-point or parallel-lines system) aren't always easy to implement perfectly in practice (due to the long list of elements above). But this long list of "elements" present challenges to any system. The challenges of perception, vision, and alignment are ever-present at the pool table, regardless of the system one might be attempting to use.

Now, to judge whether or not your version of CTE is "geometrically consistent" or not, we would need a clear description of your version of CTE. I have heard and seen many versions of CTE over the years. Several descriptions, and one demonstration, of versions of CTE that have been offered over the years, can be found here:

http://billiards.colostate.edu/threads/aiming.html#CTE​

None of these versions of CTE satisfy the definition of "geometrically consistent" above. I'm not saying your current version of CTE even closely resembles any of the posted versions, nor am I saying that none of the versions of CTE actually work "in practice" for some people. However, no version of CTE I have seen or heard to date can be described as geometrically consistent, IMO. I would still like to read a description of your version of CTE. How is your document coming? Weren't you working on something? Would you be willing to post a short and clear set of steps (with or without diagrams) that describes how you version of CTE works in theory? FYI, here are examples of the style of description (and illustration) that enable a "system" pass the test of "geometric consistency":

bisect-pivot-and-shift aiming system
contact-point-to-contact-point or parallel-lines system​

FYI, the version of double-the-distance described at the beginning of this thread is NOT "geometrically consistent." It breaks down as the balls get closer. Therefore, even "in theory," the system isn't perfect. Any system can break down in actual implementation.

I hope you don't take any offense with this post. I mean no disrespect whatsoever. I hope we can continue this discussion and better understand how your version of CTE works (in theory and in practice), whether or not it is "geometrically consistent."

Looking forward to your thoughts (and the thoughts of others),
Dave

 

[dr_dave]

I'm a little late to this thread, maybe because I'm not too big on "systems" in general. This particular one works quite well and is very accurate. Probably great for practice drills etc. There is only one problem. It is UNWORKABLE in game situations. Yes, that's what I said. Unworkable! Try using this system a few times in an actual game when you have a three quarters length table shot. You'll drive yourself crazy trying to find that perfect spot to hit the object ball. And any momentum you had will be lost as well, as you stare down at the faraway ball. Actually anything half a table or longer will be tough to figure accurately. And only slow you down.

My best guess is that if you tried to use this system exclusively on long shots, you'd miss more than you make. Up close to the object ball it's okay but still not the best way to play pool IMO. When you've been playing pool long enough (as most of you have) that little computer in your brain that has seen every shot thousands of times is your best ally. You know instinctively where to aim without needing to do any conscious calculating. sure you might take a look at the pocket on a tough cut shot just to get your bearings, but that's about it.

Sorry if I burst anyone's bubble but I guess that's how I roll. I've been banging pool balls a long time and I will always tell it like it is. This is one place I hold nothing back, especially when it comes to pool advice. See you down the road. Now can I get a gapper till next time. :grin:

Great points! I think most people (even the "math guys") would agree with you. Like I have written several times in this thread, I think most of these systems are just curiosities and tools to help beginner players get in the "ball park." High-level pool is more about perception, feel, psychology, and consistency, all of which can develop completely only with lots of successful experience and practice.

Regards,
Dave

 

[jay helfert]

Great points! I think most people (even the "math guys") would agree with you. Like I have written several times in this thread, I think most of these systems are just curiosities and tools to help beginner players get in the "ball park." High-level pool is more about perception, feel, psychology, and consistency, all of which can develop completely only with lots of successful experience and practice.

Regards,
Dave

You're the man Dave! You said the magic word - FEEL! Although the other words you used are good also :wink:. In my as yet unpublished treatise on pool, I say early on that pool is a game of "touch and feel", not geometry. Everything changes dramatically depending upon speed of stroke, english applied and other variables. And I know now that you know that!

 

[dr_dave]

You're the man Dave! You said the magic word - FEEL! Although the other words you used are good also :wink:. In my as yet unpublished treatise on pool, I say early on that pool is a game of "touch and feel", not geometry. Everything changes dramatically depending upon speed of stroke, english applied and other variables. And I know now that you know that!

You mean you don't think I'm am just a "math guy?"

I'm glad you now know that I also appreciate the "touchy-and-feely" part of pool. :wink:

I appreciate your post. I look forward to seeing your "treatise" some day.

Thanks,
Dave

 

[SpiderWebComm]

Dr. Dave:

About 70% of what you have listed about CTE in your aiming system is inaccurate or incomplete. Using it as a CTE is like having an encyclopedia collection from A-H and thinking you have the entire edition.

You can't use your incomplete information as a cite for you saying CTE isn't geometrically correct. Based on the info you have-- I see why you'd draw that conclusion. However, it's very very incomplete (which is why I asked if anyone wanted to outline their understanding of the info). When someone like me reads that page, I shake my head because there's a lot that's not there.

That's why neither you or PJ (no offense, I promise) say CTE is geometrically incorrect--- you say so with inadequate knowledge. That was my point. It's not a knock or a jab. I knew PJ's understanding of CTE was your site--- which is why I made that post earlier.

The best piece of info you have on your CTE site is my shot circle diagram. You mentioned before that made no sense to you -- I can help.

Let me know your questions and I'll answer them. I think once you get up to speed with that info, I think you'll start taking it a little more serious.

Dave

P.S. It's not "my version" of CTE you need to know -- I didn't invent anything... it's "CTE" in general you need. You only have the "CT" of the CTE.

 

[TheConArtist]

just aim the edge of the cueball to the objectball.

 

[dr_dave]

About 70% of what you have listed about CTE in your aiming system is inaccurate or incomplete.
... However, it's very very incomplete ... When someone like me reads that page, I shake my head because there's a lot that's not there

Spidey,

I totally agree the posted CTE information is not "complete." If it were, we wouldn't have all of these questions and doubts. (BTW, for the record, none of that information is "mine" ... I have just provided links to and quotes from info provided by others.) Unfortunately, these are the only demonstrations and descriptions of CTE that have been offered to date, to my knowledge. You had posted some videos in the past, but you removed them (I assume because you thought they were not very "representative" of the system). If even you can't create a simple step-by-step description and/or video that demonstrates the system (and you seem to be a CTE expert), how can you expect PJ, me, or others (who you claim don't really know CTE) to write a description that you will be happy with? :frown: Neither PJ or myself have tried to describe CTE (as far as I know), because the information that has been posted by others, and the information shared to me by Hal, Stan, you, Ron, and others, has not been clear and complete enough (intentional or not) for me to provide a convincing description or demonstration.

I think if CTE is to be taken seriously, someone who truly knows CTE should explain to us in simple terms what it is. Whenever somebody tries to explain what it is (e.g., with the quotes here), you and others claim the information is incomplete or invalid. If that is the case, please provide us with better information!!! Without better information, it is pointless discussing something which has not been defined properly.

Let me know your questions and I'll answer them.

Thank you. Here is the only question I have, until I have a better understanding of what CTE really is:

Would you please be willing to post a short and clear set of steps (with or without diagrams and demonstrations) that describe what CTE really is?

I have asked this many times over the years of several people. I have quoted the only answers I have received. I am hoping you can finally settle this. I don't think I'm asking for much. I have spent many hours on the phone with CTE proponents, and I have read thousands of posts and private e-mails about CTE over the years, and I still don't know what CTE is (according to you). Please educate us. Please! I think I have put in my fair share of effort over the years. Now, I'm asking you to put out only a small amount of effort. FYI, here are examples of the style of description (and illustration) that I am hoping to see:

bisect-pivot-and-shift aiming system
contact-point-to-contact-point or parallel-lines system​

If you could provide a straightforward description of CTE, I'm sure many people would appreciate it. They might even be willing to learn more by paying an instructor to help them apply the information.

Please provide us with some concrete, accurate, and useful information. If you do, I would be more than happy to add to or replace the current info I have quoted.

Respectfully, seriously, and with strong interest,
Dave

 

[dr_dave]

just aim the edge of the cueball to the objectball.

Thank you for sharing the diagram. It looks like a variation of fractional ball aiming to me. As with most "systems," the tough part is judging the angle of the shot and perceiving in 3D what the diagrams show so well in 2D. Also, there are many shots that can be missed with only four lines of aim (without intuitive compensation and "feel" relative to the reference positions). Having said all of this, I still believe there are many benefits to systems like this, especially for beginners.

Regards,
Dave

 

[Patrick Johnson]

Your geometrically correct systems can't show you the correct alignment in practice, unless you get lucky.

You mean unless the system is applied exactly, which is difficult for human players with human faculties. But "geometrically incorrect" systems like CTE can't show you the correct alignment even if you're a robot following the system steps exactly.

CTE is a geometrically correct system....no less geometrically correct than any other system on earth.

If so, the part of the system that makes it geometrically correct has not yet been described. I believe it doesn't exist. You're welcome to prove me wrong by describing it, but I suspect "it's not yours to tell" or some other familiar excuse.

pj
chgo

 

[SpiderWebComm]

You're exactly right. It's not mine to post. I promised when I learned the move, I wouldn't post it.

So PJ/Dave: You should take some time to find someone willing to tell you. The problem is, from what I gather, the few people who know everything aren't fans of yours and it's not my place to cut the hands that feed me.

I'll bap the ball in your court and let you guys work it out. Forget that stupid aiming landing page for a moment. Type up a post with step by step instructions of how you'd go about making a shot. I know, you know and everyone knows it'll be wrong--- but at least I'll tell you the parts you have to work on or are incorrect. What's wrong with that?

I always wonder why when someone like me asks either of you to explain your understanding of it--- you spin it back to the person who asked the question for them to do the same. I know this stuff--- I'm offering to help either of ya.

So, I'll ask again--- make a video or post some info on how you think this stuff works--- and I'll critique it.

 

[Clark_the_Shark]

Here's the best description of CTE that I could find directly from a student of Hal Houle. I think it has been posted before, but it might have been glossed over...

http://www.youtube.com/watch?v=Bi_UCD-eD00

Spider... I agree with Dave here, first the variable needs to be clearly DEFINED before any progress can be made toward an answer, otherwise people end up explaining two different things because their definitions differ (as you have clearly pointed out).

And second, you can't expect people to intelligently discuss any system for which they know little or nothing about, AND THEN not give any information that enhances their knowledge of the subject and keep telling them that they are wrong! It's not fair.

And I just posted at the same time as your last post, so I didn't see your reply... but what you are in essence saying is "You guys guess what it is, and I'll tell you if you are Warm or Cold." That's not cool either.

 

[SpiderWebComm]

But "geometrically incorrect" systems like CTE can't show you the correct alignment even if you're a robot following the system steps exactly.
chgo

So.... what are the steps? ? ? ? ? ? ?

 

[SpiderWebComm]

Here's the best description of CTE that I could find directly from a student of Hal Houle. I think it has been posted before, but it might have been glossed over...

http://www.youtube.com/watch?v=Bi_UCD-eD00

Spider... I agree with Dave here, first the variable needs to be clearly DEFINED before any progress can be made toward an answer, otherwise people end up explaining two different things because their definitions differ (as you have clearly pointed out).

And second, you can't expect people to intelligently discuss any system for which they know little or nothing about, AND THEN not give any information that enhances their knowledge of the subject and keep telling them that they are wrong! It's not fair.

And I just posted at the same time as your last post, so I didn't see your reply... but what you are in essence saying is "You guys guess what it is, and I'll tell you if you are Warm or Cold." That's not cool either.

Clarkie:

I totally agree. Believe me. What else can I do though? I either let them know what's wrong or parts missing or I just let them discuss this stuff as if they know when they don't. I will enhance their knowledge if they outline what they know... I'll let them know the parts missing.

That video is very, very basic. He's a good friend of mine but there's a lot missing from that video:

1) The pivot
2) The edges
3) Bridgehand placement **bridgehand spot

I make these posts asking these guys to explain because they state in definitive terms that CTE is not geometrically correct; however, neither of them really knows what CTE is. Therefore, they should find out the info or refrain from making claims that they know nothing about.

Someday in the future, when Hal passes and if I can get an ok from another guy... I'll light this board up with info. Until then, I'm not posting anything because I made promises not to. What can I say? I'm a man of my word.

 

[Clark_the_Shark]

That video is very, very basic. He's a good friend of mine but there's a lot missing from that video:

1) The pivot
2) The edges
3) Bridgehand placement **bridgehand spot

Those things "missing" sound a lot like Colin Colenso's BHE stuff, which all depends on Pivot Point (which ends up being pretty complicated to compensate for during actual gameplay)

 

[8pack]

cte

SpiderWebComm...Dave i was wondering if your shooting lets say a shot that is past a halfball hit.Could there be three different spots where to place the bridgehand and if you know something about cueball position on the table and the cut angle you will know where to place the bridge hand?

I know nothing on cte but just trying to learn it so what im posting might be way off.

 

[CocoboloCowboy]

Recently, Don Smith sent me a document describing a double-the-distance aiming system. Don asked me to post it and see if people think it is new or not, and to get feedback. Here's Don's complete document:

"An Aiming Point Method For Pool" by Don Smith, August 2009​

Here's how it works (per the diagram below):

1. Find the point where a line from the cue ball will intersect the object ball.
2. Find the point where a line from the pocket (or other target) will intersect the object ball.
3. Estimate the distance between these two points.
4. Double this distance to find the aiming point.

Per the diagram below, Don's system recommends sighting through the center of the CB (and not along parallel lines, as implied by traditional double-the-distance and contact-point-at-center-of-ball-overlap methods). Because of this, the system doesn't work well when the CB is close to the OB (see error "E" in the diagram below), but it works fine when the balls are farther apart, for all cut angles.

It does take a little practice estimating the distances, but you can use your cue tip to help. See the document for more info and examples.

This look like something I saw in Freddy The Beards,'s NEW DVD, believe he called it the Sailor Barge Methoid, you can get the DVD's at Pool N Darts , or Freddy's site.

 

[JoeW]

It appears to me that Eric's goal was to clearly show Hal Houle's CTE guidelines. In my viewing I think he accomplished his goal. Given that this information is now on the net, one is not telling Hal's secrets out of school. Except in so far as one might want to add to or perhaps correct Eric's understanding.

There is enough information in Eric's video for me to understand what it means to use CTE. I have reduced his video to a set of statements or guidelines for how to use CTE for cuts less than 30 degrees, 1/2 ball hits, and for relatively thin cuts. If I can do this, anyone could deduce the suggested guidelines for CTE. To say that CTE has not been clearly stated is simply no longer true. View Eric's presentation and the suggested guidelines are clearly and consicely presented.

At this point it would appear that comments about how to pivot, perceptions of edges, and exact hand placement are refinements and not the revelation of a secret aiming system. If someone should think that their particular contribution about one or more of these three topics is in some way a secret then my suspicion is that they are attempting to use some small amount of infomation added to Hal's approach for personal gain. I suspect that these three refinements could be derived by anyone who studies the approach in a serious manner.

While there are people who think that math or geometry needs to be used to "prove" what one can or cannot do on a pool table I suspect that these people often deceive themselves in a simple belief in a reductionistic aproach that does not encompass all of the variables that need to be included. To understand and to play pool well requires much more than a knowledge of physics or math. If pool playng could be reduced in this way I would find it much less interesting.

 

[dr_dave]

So, I'll ask again--- make a video or post some info on how you think this stuff works--- and I'll critique it.

OK. It sounds like we need to start with something. Here is the best I can do at this point, with the limited information available. This is based mostly on the the info posted here (including the video from eezbank), and from what I have learned from Hal, Stan, you, and past threads over the years.

DRAFT DESCRIPTION OF THE CTE PROCEDURE
​

For a “thick hit” (a small cut angle less than 15 degrees) to the left:

1. Align the cue 1 tip to the right of the CB center through the right edge of the OB.
2. Place the bridge hand down with the cue exactly along this line, using a 10-12 inch bridge length.
3. Pivot the cue (without shifting the bridge at all, so the cue rotates about the fixed bridge-pivot point), until the cue is pointed directly through the center of the CB.
4. Stroke perfectly straight along this line.

For a “half-ball hit” (close to 30 degrees) to the left:

1. Align the cue through the center of the CB and through the right edge of the OB.
2. Place the bridge hand down with the cue exactly along this line. The bridge length can be anything for this shot since there is no pivot.
3. Stroke perfectly straight along this center-to-edge line.

For a “thin cut” (more than 45 degrees) to the left:

1. Align the cue 1 tip to the left of the CB center through the right edge of the OB.
2. Place the bridge hand down with the cue exactly along this line, using a 10-12 inch bridge length.
3. Pivot the cue (without shifting the bridge at all, so the cue rotates about the fixed bridge-pivot point), until the cue is pointed directly through the center of the CB.
4. Stroke perfectly straight along this line.

If you follow the procedures above exactly, you will make shots within certain limited ranges of angles. However, you will miss most shots outside of these limited ranges, unless the OB is very close to the pocket and/or the pockets are huge (so significant "pocket cheating" is possible). Now, you can make the procedures work if you compensate a little as the cut angle changes. For example, you can adjust your bridge length (this has a huge effect on the results of the pivot step per Diagram 4 in my December ‘08 BD article, which is included below), modify the starting tip position a little, pivot slightly less or slightly more relative to the CB center, and/or you can shift your bridge hand slightly during the pivot (e.g., by pivoting with your hips or body) to create a different effective pivot point farther back or closer up from the bridge. You can also “air pivot” where you make subtle changes to all of this stuff intuitively as you come down into the shot (in which case you place your bridge and cue along the required line of aim of the shot with center-ball alignment, without using the separate tip-offset-and-pivot steps). Then, the system can work perfectly for any shot at the table, provided you can judge, perceive, and apply the subtle differences from one shot to another (in which case you don’t need an aiming system).

Hopefully, this is enough of a start to create some useful discussion. I look forward to input from you and others so we can refine this procedure to have it better represent what you think CTE is.

Thank you for your time,
Dave

PS: I put a lot of time into this, so please respond in a constructive way (even if critically constructive), so we can make some progress. In other words, please contribute some of your knowledge and information.

 

[dr_dave]

Those things "missing" sound a lot like Colin Colenso's BHE stuff, which all depends on Pivot Point (which ends up being pretty complicated to compensate for during actual gameplay)

Actually, English creates a whole new set of aiming issues. The version of CTE we are discussing here is concerned only with center-ball hits. Let's please keep the focus on that first, before we even mention English. FYI, Colin's methods, along with other approaches for compensating aim with English can be found here:

http://billiards.colostate.edu/threads/aiming.html#compensation​

but let's not discuss those in this thread (not for now, anyway).

Thanks,
Dave

 

[JoeW]

Dave's presentation of the suggested guidelines with the addition of bridge length appears to summarize what Eric presented. Apparently he has added some additional information from other sources re bridge length. The figure shown is not exatly what is described by Eric who appears to suggest beginning the aiming process by placing the cue tip one cue tip (whatever that means given various cue tip sizes) off center (in what would appear to be "outside" english). The player then shifts as described by Dave.