The cue ball is taken easily on a three-cushion bank shot through the "magic spot", when added to the accuracy of the "Corner 5 System".
In this first diagram, the white cue ball is the origin point of the stroke. The cue ball outlined in red is what is known in billiards as a "mirror image" ball (along an opposite rail equidistant from its cushion and the mirrored ball). The mirror spot is also the destination point of the multi-rail bank.
Specifically, the "magic spot" is at "x" along the first line of the shot, and rests approximately 1½ to 2 ball widths from the first diamond from the side pocket.
Memorize this simple rule for multiple cushion banks taken from a variety of places on the table--a cue ball that passes over the magic spot (generally when taken with natural or "running" english) will cross over its mirror image point on the table!
To find the magic spot on a particular table to adjust for "local conditions" is simple. Mark a spot 1½ ball widths from the first diamond adjacent to a pocket. Align the cue ball with a corner pocket and shoot over the magic spot to and see whether the cue ball sinks in the mirror corner. If you come short or long of the corner line, you can adjust speed or english or even the magic spot closer to 2 balls' width from the cushion. Make the corner ball frequently and you have your "magic spot" and "magic speed and spin".
Note: Adjustments are often necessary as with other bank and diamond calculation systems. Not to mention worn and torn table cushions!