Consider a pool pocket of 4.5 inches. That is the width of two balls. A player aiming a center ball shot at the middle of the pocket has about a half ball margin of error on each side of center. Now consider a half ball shot of medium speed that you need to put outside side to alter the angle off the rail. We know that outside side will throw the object ball towards the far side of the pocket. A tip of outside side will alter the object ball path up to 5-6°. A single degree of deviation on a 5 foot shot equals an inch. If the shot is 2 ½ feet from the hole the ball path would be altered by a ball width minus some cue ball deflection. So in order to compensate the shooter adjusts the original aim line. By aiming just inside the undercut side of the pocket, the squerve uses the full 4.5" of the pocket to maximize error potential. If the shooter somehow twists his cue and ends up with no outside side the ball would go into the near side. If the ball works as compensated for, the result is a center pocket hit. If the cueist mishits and adds extra side, the deflection will be larger and the wider angle adds undercut to the shot line but additional throw to the shot. The entire pocket is available to catch intentionally applied english. On a center ball shot half of the margin of error is allotted to a mishit to the left and the other half to errors to the right. No compensation for either error is factored into the shot alignment. There is a ball’s width of space in total to be divided between the left or right mishits. In the adjusted aim scenario, if the shot, was a planned left spin scenario, there is no need to allocate any pocket space for a potential right english mishit. The center ball scenario has 2 ¼" plus a half ball or 1 ⅛" which together provide 3 ⅜ " of pocket space to accept the ball, on a left mishit. The intentional choice to put english on the ball and adjust for it ahead of time lets us allocate the entire pocket width, or 4 ½" to a shot with left english.
In golf, pros often use what are called shaped shots. Since golf holes will dogleg either left or right a shaped shot can complement the shape of the hole. Beyond that many pros choose a shaped shot on a straight hole. Since a straight drive is harder to hit than a curved shot they pick a curved shot. Unlike a golfer who tries a straight drive and has half a fairway to either side to catch mishits, the deliberate choice of a shaped shot increases margin of error. The golfer may choose to shape a shot from left to right. First though he compensates for it in his aim. His target is the fairway center and so he aims at the left edge of the fairway visualizing the ball curving into the middle. If he mishits and the ball fails to curve, the ball will be in the left side of the fairway. If he mishits and gets extra curve on the ball there is the entire width of the fairway across which the ball can travel before he misses the fairway to the right. By allocating all landing space to balls hit with a left to right path the error margin previously allocated to right to left mishits can be shifted to a deliberately chosen off center shot.
TOI was CJ’s application of this principle. The concept was to minimize the amount of side, to minimize throw and in fact to make sure the action of the cue delivery was targeted to a firm strike deflecting the ball slightly compensating for the off center hit. In order to minimize the side he started from a compensated ghost ball line. The cue is shifted off the line to the inside side of the shot. So on a cut to the right that means the butt of the cue is shifted to the right followed by the tip, but to a lesser degree. The line the cue is now on, compared to the original is that it points farther left than the original line. The cue line passes just to the inside side of the cue ball center minimizing how much inside torque is applied to the ball. CJ emphasized that there was no effort or intent to spin the ball. He said he simply cued to the inside. His description though emphasized acceleration through the ball and that the chosen compensation for the shot line included adjusting for deflection. CJ compensates for the overcut created by the inside shift. The original starting reference line, before the shift, is a ghost ball line aimed at the undercut side of the pocket. The subsequent shift and repositioning of the cue line to a point farther left of the original ends up targeting the middle of the pocket. This is the pool equivalent of a shaped shot. CJ later tacked on an aiming system. However, any aiming system can adopt the shaped shot concept to maximize allocation of pocket zone shot capture capability. This is the starting point for a much more sophisticated approach to potting a ball.