If your statement is true, why aren't they dominate in every sport? Why isn't the girls basketball team playing OS tonight? Why hasn't the softball team excelled? Why is the soccer team co-ed? Why hasn't football and baseball dominated as well?
They do not pick and chose only good athletes! Come on! I am sure they do not have a part of the admissions process where the potential student at Grace picks up a ball and shows the coach what they can do. This is a silly argument on your part. It isn't like Grace made the decision to play Single A ball in this district...just like Tellico Plains did not choose to be in this district next year.
Small school athletics is a 5-7 year cycle anyway. There a not many teams that are consistantly good year in and year out. I would say this would be true of the boys basketball team at Grace next year. The lose of Pridemore and Slusher will be huge, and Grace will not be as good as they are this year. That is just life.