It really comes down to knowing your equipment and knowing/trusting yourself. Sometimes, even if you do throw a bad shot, if you realize HOW you threw it bad, and what the ball did you can get a measure on what you might need to adjust. It's all a confidence thing. There's really just not too much room for emotion. What you've already thrown is done. Watch it, notice it, learn from it. What happens on the pin deck will happen. Watch it, notice it, learn from it. Once you have released the ball, watch the reaction down the lane, through the pin deck and even how the pins fall. All of that is GREAT knowledge for future shots and you should take advantage of it. It's like religion, once you believe (in this case in yourself) it's always there.
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First one to leave 15 ten pins wins!