In general, it's false that sub-problems of a problem with an optimal solution are optimal themselves.(Wikipedia's article says the same differently: "In computer science, a problem that can be broken apart like this is said to have optimal substructure.", implying some problems can't be broken apart like that). Also see: https://en.wikipedia.org/wiki/Optimal_substructure
Maybe Go has this property of optimal substructure. Maybe it doesn't. I don't know, but it sure isn't immediately evident.
In general, it's false that sub-problems of a problem with an optimal solution are optimal themselves.(Wikipedia's article says the same differently: "In computer science, a problem that can be broken apart like this is said to have optimal substructure.", implying some problems can't be broken apart like that). Also see: https://en.wikipedia.org/wiki/Optimal_substructure
Maybe Go has this property of optimal substructure. Maybe it doesn't. I don't know, but it sure isn't immediately evident.