Bison weren't too smart in the first place...they could be chased off the edge of a cliff
Whitetail will look UP to find you. They know something is just not right.
I had Axis deer about 70yds away hang out/walk around in a small thicket ALL DAY. I was in a box blind BUT the wind was blowing right through it, and toward them. I think scent was keeping em there.
Now, I don't worry about scent when stalking Antelope on the plains, but when I'm in the woods, the whitetail's backyard, trying for a bow shot, I'm taking all precautions.