Half-ball contacts ensuring the run of the object ball along the usual half-ball contact course, can often be effected when the stroke is not a half-ball one. The red ball, for example, may be on the spot with the cue ball rather too widely or narrowly placed near a top pocket shoulder to leave an ordinary half-ball in-off into the opposite top pocket.
But by playing gently with running or check side and aiming rather fuller or finer than half-ball the half-ball contact will still be made, as the cue ball will curve slightly before reaching the red, and the object ball will thus be driven into favourable position for continuing with a middle pocket in-off.
Even when the cue ball is several inches along the top cushion or one or two inches down the side cushion, the same contact can still be made - by means of a fairly gentle half-masse stroke, which curls the cue ball, still more, in the one case, and a rather fine running side stroke in the other. These are much better strokes than harder and check side strokes from the same position, as they leave the middle pocket position just as though an ordinary half-ball stroke had been played, and present the further great advantage of pocket side.
The strokes described are equally useful when played from near the middle pockets on to the red on the spot and also when played from baulk into the middle pocket, the result in each of these cases being to drive the object ball to the top cushion and back along a line somewhat parallel with the side cushions. The finer than half-ball stroke from above the middle pocket is, however, made with check, as this is pocket side from that position.
It is always wise gradually to lead up to another required position, rather than to endeavour to force the desired lie of the balls by means of a problematical shot, however appealing such a shot may be. Perhaps the immediate shot, without being at all difficult in itself, requires a little forcing or other compensation which may operate in a manner inimical to the maintenance of position, whereas a near fine in-off or a long slow one may leave a simple ball to ball cannon or half-ball in-off.
In watching the play of professionals it will be noticed that they are never in a hurry to get a wayward ball immediately into play. They bide their time, scoring experimental in-offs all the time and presently a little extra strength or a little deviation from the natural angle in the run of the object ball yields them the opportunity for which they have been waiting.
For instance, a double baulk may have been just missed by the opponent so far as his ball is concerned and this ball may be a little way up the table. The professional plays ordinary in-offs until he has exactly gauged the strength necessary to bring the white near to the baulk line and with the next stroke he makes a cannon on to the red, with the second he pots the red, wheeling his own ball round in so doing, with the third he pockets his ball off the white, which he guides to the middle of the table, and before the majority of the spectators know what has happened he is at the top of the table merrily alternating cannons with pots.
Even when the top of the table has been thus strategically gained, the necessity for measured certainty in lieu of retarding haste is often realized by the good player who may be seen apparently dallying with cannons when there is an easy pot on or making a somewhat sporting" pot "when there is the simplest of cannons close to hand. It is all a question of position and of the practically certain continuance of the sequence. In the one case the white ball may not be so near the spot as is desired and it has to be gently edged in that direction by means of one or two gentle cannons. In the other case the white ball may be already nicely placed near the spot and a cannon would disturb if.