What is Communication?
When checkers lie six of fewer pips apart, they are said to communicate — a single number on a die enables the rear checker to move to safety on a point with the front checker. Put your checkers in communication with each other when you seek safety or want to cover blots.
What is Control?
Control compliments communication. Checkers spaced relatively far apart control a larger portion of the board. Seek control when it is your opponent who requires safety.
Black to play 6-1.
Black has three plausible plays: (a) 7/1, 6/5; (b) 21/14; (c) 21/15, 6/5. Because it is white who leads in the race (92 pips to 118 after black moves) and therefore requires safety for the blot on black’s nine point, black should seek control.
The safe play (a) does nothing to achieve this and should be rejected. Both the other plays gain control of the midfield. Play (b) leaves two fewer shots. Nonetheless, (c) is superior for three reasons:
- Black’s checkers communicate, so that if white hits (with anything but 6-3, 6-4, 6-5, or 3-3), black gets return shots.
- Black controls one more point (a blot on the 14 point doesn’t control the 14 point).
- Black diversifies the spares in his home board, activating a builder on the five point.
Black to play 2-1.
This position resembles Problem 55 of Joe Dwek’s Backgammon for Profit. Here, black cannot create communication between the checker on the 14 point and the two on the 21 point. But once again, it is control which black should seek.
Though 14/11 is safer, leaving only 11 shots, black should move 6/4 or 7/4.
True, on the 14 point, black’s blot can be hit by 15 rolls. In exchange for the four estra shots, however, black gains control of three extra points (the 11, 12, and 13 points). Such control translates to a direct shot next turn if white rolls 1-2, 1-5, 1-6, 2-3, or 2-5. (5-6 produces a direct shot either way.)