RE: 20MPH winds
I think it depends on where i'm hunting & direction. Regardless of how much wind we have there are spots along the river bottom that'll still be fairly calm. So on windy days i'll usually go down to the river and hunt a stand near some conifers or heavy timber, and hunt like normal. Sunday was a good example... it was windy, 50-60mph gusts, 30-40 straight winds. But down on the bottoms there was hardly anything.
But I've seen plenty of good deer movement in heavy wind as well... where the wind is blowing the fur around on the deer, and dust clouds & tumbleweeds are traveling along. The hunting can still be good... it's just harder hunting