This comes out of the Joe Tucker book of drills. This drill (or actually a more difficult variation) is called the Karen Corr drill, or sometimes The Rail Workout. The object is to make the balls in order, can't contact another ball.
Ideally, one would you use draw/outside english for one half of the table and forward/inside english for the other. But, this easier ruleset is a good way to start it off, whichever route gives the best opportunity to continue the drill.
It's been a long time since I've attempted this drill and some of these shots were giving me plenty of trouble earlier in the evening. So I went back to it and completed it! I was able to use all 3 types of positional shots as well.
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