I can't tell you how Stan's version of CTE works, because I haven't seen it described in detail yet, and I haven't seen the DVD yet. However, I do look forward to viewing it to see if it adds any significant insight to the CTE landscape. I hope it does.
However, for
the three versions of CTE that have been described in detail and/or demonstrated, I think I have explained how and why they work, to the best of my ability. Here is my explanation (from the
CTE resource page):
If you follow the
procedures literally and exactly, you will make shots within certain limited ranges of angles (for more info, see
limited lines of aim). However, if you don't vary the alignment or pivot (see more below), you will miss most shots outside of these limited ranges, unless the OB is very close to the pocket (so it can be cheated slightly) and/or the pockets are huge (so the margin for error is larger than normal). The difficulty is in applying the subtle differences necessary from one shot to another. However, even if a person is not good at judging these differences, CTE still might be beneficial for the reasons summarized
here.
Many "challenges" relating to "aiming systems" are described and illustrated in my
November '08 and
December '08 BD articles. These difficulties certainly apply to CTE. Here's a good experiment you can use to test whether or not you understand how to apply CTE (or any pivot-based aiming method) effectively:
Shot "A" is about a 10-degree cut, shot "B" is about a 15-degree cut, and shot "C" is about a 20-degree cut. All three shots fit into the "thick cut" category of CTE. Also, the CB-to-OB distance is the same for all three shots. Here's the CTE aiming procedure for a "thick cut" shot, per the 3rd version of CTE above, as I understand it:
1.) ALIGN: (for thick cuts): Start with your cue parallel to the CB-center-to-outside-OB-edge line (CTEL) with the tip pointing at the outside edge of the CB.
2.) PIVOT: Then pivot your tip toward the pocket until it reaches the CB's center. The "effective pivot length" you use during the pivot should be the distance from the bridge to the OB.
Since all three shots are "thick hits," and since the CB-to-OB distance is the same for each, the "effective pivot length" is also the same for each (assuming the bridge length is the same for all three shots). So the pertinent question is: What do you do differently with the alignment and/or pivot steps of CTE to pocket each of the three shots? There are several possible answers. You can:
1.) Change the initial alignment slightly (e.g., by shifting your eye alignment so the perceived cue alignment and/or parallel shift is different)
or
2.) Change the amount of the parallel shift (before the pivot) so you don't quite go all of the way to the perceived CB edge (e.g., shift a given number of "tips" instead)
or
3.) Pivot a slightly different amount (e.g., not quite to center, or just past center).
or
4.) Change the "effective pivot length" slightly (e.g., by adjusting your bridge length or by shifting/tilting your bridge during the pivot).
Options 1 and 4 are probably the most common approaches. The diagram below (from my
December '08 article) shows how a change in "effective pivot length" changes the amount of cut. In the diagram, I am showing two different bridge positions, but this could also represent two different "effective cue-pivot-points" created by a non-rigid-bridge pivot method (see more below).
If using a "mechanical pivot" (i.e., pivoting after placing the bridge hand down), one way to vary the "effective pivot length" is to vary the bridge length (as implied by the diagram). Another is to shift, rotate, tilt, or deform your bridge hand during the pivot as you shift your body (AKA "hip pivot"). Here's an example of this, posted by Colin Colenso, where the "effective pivot length" is much longer than the bridge length:
Another way is to use an "air pivot," where you pivot the cue and/or entire body before placing the bridge hand down. In this case, you can easily create any "effective pivot length" over an extremely wide range. Sometimes, the "effective pivot length" is referred to as the "shot arc." Here is a demonstration of how some forms of pivoting are used in conjunction with CTE and other pivot-based aiming methods:
CTE pivot demonstration. For more info concerning pivoting, "air pivot," and "shot arc," see
Spidey's blog.
The difficulty is in judging how much to change the initial alignment or "effective pivot length" to pocket balls requiring similar, but slightly different, amounts of cut. Many of the CTE proponents will say you don't need to know where the pocket is, or take into consideration the necessary amount of cut (other than to judge a "thin hit" vs. a "thick hit"), but this obviously cannot be the case. Maybe people who seem to use CTE effectively must at least sense where the pocket is (even if they don't look at it), or maybe they just have a feel for how much cut they need to pocket the ball. This sense or feel could influence their alignment or "pivot" in intangible ways that are difficult to describe or illustrate.
With all pivot-based aiming methods, the choice for "effective pivot length" must vary with the distance between the CB and OB, as illustrated by this diagram from my
November '08 BD article:
As you can see, with a fixed alignment and pivot, the cut angle is radically different for different ball distances. Interestingly, with the exact same initial alignment and pivot, two of the three balls can be potted if the pocket happens to be at points "a," "b," or "c." This would actually be a good proposition shot. Approach somebody who doubts pivot-based aiming systems and bet him or her you can make two radically different shots (e.g., shots "A" and "B" in the diagram) with the exact same initial alignment and the exact same pivot. You can even have the doubter shoot the shots for you, as long as his aim and stroke are reasonably good. If the balls are lined up to take advantage of the effect shown in the diagram (i.e., if the balls are lined up so the corner pocket is at point "a" relative to the balls), both shots will go and you will win the bet.
BOTTOM LINE: All CTE variations require changes in alignment and/or effective pivot length as the cut angle and shot distance change.
Regardless of which "aiming system" you might use (even if you just "see the angle"), you still need to practice to develop and improve your "visual intelligence" and consistency, and you need to actually focus on aiming the shot. Many aiming systems can help some people do this (for more info, see
benefits of "aiming systems"). Also, when you use English, you will need to
compensate your aim to account for squirt, swerve, and throw.
Regardless of all of this, CTE does work for the people who can use it effectively, and CTE does offer many potential benefits to some people.
Regards,
Dave