I hunted from one last season, and had a 6 pointer 15 yards away. He looked my direction a couple of times, and am quite certain he saw the blind, but he didn't spook. In the blinds defense, I had the mesh window out of it as I was using a muzzle loader. I believe he was skittish of the black hole the window created. Seems to me as long as you brush the blind in a little bit, and even more importantly have an overhanging branch across the top to break up the roof outline, they pay little attention to blinds. I believe also that if you are in the middle of a field, no brushing in is required, just set it up and hunt. I have heard that the idea is not to "surprise" the deer as they come down the trail.