A customer called to say that a natural gut string job I did for him nearly a year ago broke before he even used it. He has a pair of racquets, uses 1 till it breaks, then expects to use the other. In this case it was sitting for about 11 months. Personally, I am not surprised when this sort of thing happens since every natural gut string job sitting in my closet has done the same thing given enough time. My question is: What causes this and is there a storage regimen that can prevent it?