It IS potent stuff. In addition to the flavor, it imparts a serious yellow color to the dish. If the recipe doesn't have a lot of liquid in it, bloom the safron in some warm water before adding it to the recipe.
As to what it tastes like... I can't describe the taste of someting you've never tasted by trying to relate it to something you have eaten (tastes like ???????). I don't know that saffron tastes like anything else.