As luck would have it, I do not know how to play backgammon, so I cannot answer your question in the way you want me to answer it. However, I can give you an example with a class of game I know how to play (i.e., card games), but first I think that it is important to recognize an important aspect about all games that humans play: the rules by which one play are decided purely as a convention of playing the game and there is no reason that you have to play by them except perhaps that you might not be playing the same game if you were playing by different rules. Evolution has no such conventions that limit the physical possibility except the laws of physics themselves. Thus, it is possible to have a duplicated genome in the game of evolution and still play the game where as the analogous situation of having twice as many cards of the same number and type (this is for the purpose of maximizing the number of points of correspondence between the analogs but need not be the case, especially as organisms with duplicate genomes start to diverge) would automatically disqualify you form play in any card game I know how to play. Similarly, aside from the fact that not all pairs are equally likely to mate, there are no rules forbidding individuals of the same species from mating with each other in the game of evolution, whereas in a card game one is only able to exchange cards with other player specifically designated by the rules of the game. The rules for cards-in-hand, card exchange, and other conventions of the game makes it possible to apply strategy to winning. In fact if you cheat, say by counting cards, you can guarantee your victory. The point is that it doesn't seem possible to bias evolution in the same way that you can human games. There are very few conventions which individuals have to follow in evolution; thus, all advantages you gain are "fair" advantages which is not the case with human games.
