I understand that, and , I agree that it would be a good aid for that. But, wouldn't it also work to see if people are really aiming CTE on shots?
Neil-ski:
You might have a point -- I remember reading Dave S.'s (SpiderWebComm's) vague-at-first-but-gradually-started-coming-into-focus descriptions about CTE, and he describes a "shot circle," as well as "stepping into the shot circle, and sweeping the circle." (The shot circle being that circle around the object ball, and one "sweeps" it until the cue ball comes into the field of view.)
Now, granted, I'm not a CTE user at all; I'm lucky to have been blessed with excellent 3D spacial perception, so ghostball came naturally to me even as a little 'un. But from the little I know about CTE, it seems to me that the vertically-painted laser line might be a naturally intuitive training aid to "sweeping the circle," for those inclined/need CTE.
As far as "verifying if people are using CTE on their shots," well, that's a different matter. No laser can "identify" what's going on in one's head, unless said laser is used to cut into said head to expose the contents for examination.

Methinks the final aim point is the same, regardless of how one obtains it -- whether through ghostball, fractional, or pivot-based aiming like CTE. I mean if you, I, or Spidey were to make the exact same shot on three separate tables (cut shot, center cue ball, no english), use our techniques to arrive at our final aim point just prior to pulling the trigger, and were to freeze in that position so that someone can look down our cue, as long as all three of us arrived at the proper aim point to
pocket the object ball, the sight line down all three of our cues would be to the exact same spot. I don't see how a vertically-painted laser is going to help one "tell" what aiming system he/she used, unless in the CTE user's case, the "sweeping the circle" motion was patently obvious.**
Or am I misunderstanding the question / point?
Let me know,
-Sean
Footnote** = I've seen Dave S. play at the SBE amateur event (the one Larry Price ultimately won), and while cajoling him about CTE threads on AZB, I made the funny, all in jest of course, that he looked like the turret on an
M-1 Abrams battle tank, slowly pivoting the "turret" [cue] into the shot line, and then firing.
(But hey, on the flipside of the coin, noone wants to be in the firing line of an M-1 Abrams battle tank!)