There are only two choices for this double four: (a) 13/5(2), (b) 24/16, 13/9(2).
Both plays make good four-point primes. The problem with (a) is that it leaves the rear checker badly
Too Many Choices
Unlimited Games. How should Red play 21?
eXtreme Gammon ID: XGID=-b----E-CA--dD---b-dba--AA:0:0:1:21:0:0:3:0:10
Answer and Commentary
Bray’s Learning Curve — A Great Member Benefit
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My thanks to my colleague Danny DeMeester for showing me this excellent containment position. Virtually nobody gets this problem right without a little help. As is