It isn't about if the wind is blowing hard enough to affect my shot but what the back drafts, thermals and swirlingcurrents are doing. Here at home the land is extremely flat and it is rather easy to pick a setup based on wind conditions, where I hunt a couple hours south it is very hilly old strip mine country. The swirls can ruin a perfect setup in the blink of an eye. You can have the wind in your face and have a deer snorting at you "upwind". The powder windicator really shows you what the currents are doing beyond the predominate winds direction.