Guessing on your first move is bad. The chance is the first guess/shot hitting a frog is such that on average you lose more points by guessing than shooting. And if you guess wrong, you will NOT have a "safe" shot the next time; assuming your opponent isn't totally stupid, it's your opponent who has a safe shot. And if you are unlucky, your first guess will be next to a frog; not only giving your opponent a three point advantage, your opponent will have a safe place to shoot, you still will not have a safe place (as your opponent shooting on the place you guessed will reveal a number larger than 0).