Here's a situation where a player can test their stroke. The scenario is, playing 1 pocket, you have the upper left pocket, You need both balls. The cue ball is frozen on the long cushion at the 3rd diamond, 9 ball is on the spot and the 15 ball is frozen on the 1st diamond by your opponent's pocket. You have to run the 2 balls by "Following" the cue ball 1 cushion and land within the square of that first diamond, to pocket the 15! I actually, hit the this shot TOO good and almost scratch!