The complexity comes from the fact that you have to sum up an infinite number of probabilities, because in theory you could keep playing all night without scoring another point. In a programmed statistical simulation, when two players are evenly matched, choosing 1 point causes you to win 33.3% of the time and choosing 2 points causes you to win approximately 39.8% of the time. However the better you are than your opponent, the more advantage there is in choosing to play 2 points.