Many people have opinions on the best way to dry a crop, but taking your time is not one of them. Yes, over exposure to UV rays can diminish potency (not by a lot), but over exposure to moisture will cause mold. If you had lost 5% potency on a 30% strain, and ended up with 25% thc, you're still really good. If you got mold, you lost your crop and cant even sell it illegally on the street if you wanted to.