Sancho SystemStandard counting system (S) · with biais correction

A detailed counting system built on the diamond system and the Conti system, for long–short–long bricole shots and for classic 3-, 4- and 5-cushion shots. The start and the aim are counted on the rail (on the diamond line), the arrivals on the cushion nose; the calculation always starts from the arrival: Aim = Start − Arrival (+ correction). The difference from the diamond system: the transition points on the scales do not sit on the diamonds but are shifted by measured amounts: start 50 is not at the corner but 0.18 diamond above it; the short-cushion starts are at 60 = 0.79, 70 = 1.77, 80 = 2.54, 90 = 3.15 diamonds (in the diamond system 1, 2, 2½, 3); aim 50 = 4.83 diamonds (not 5); on the 3rd-cushion arrival 40 = 3.8 diamonds (not 4). For the 4th cushion there is a detailed arrival scale at ⅓-diamond intervals, plus rules for the 5th and 6th cushions. The correction is made not according to whether the start is on the long or the short cushion, but according to the slope (biais) of the start–aim line: Correction = Biais − 6, applied as 0, ⅓, ⅔ or in full depending on the zone where ball 2 lies. The spin is maximum running spin on the equator, but for starts below 27½ and when the cue ball is frozen to the cushion it moves towards natural spin (1:30).

When? In bricole shots and classic 3–5-cushion around-the-table shots in which the cue ball goes to a long cushion, passes the short cushion, comes to the start cushion (3rd cushion) and from there to the 4th, 5th and 6th cushions. No correction is needed for 3rd-cushion arrivals; for arrivals between the 3rd and 4th cushions, the biais correction is used.