It does really depend on the deer and the neighborhood they live in. I've hunted in extremely different environments. Deep in the bowels of the Adirondacks the first whif of a man or machine will send a deer to never never land. Here in suburbia of Maryland I've been in a tree with joggers and deer in view at the same time. The joggers never aware of me or the deer but the deer locked in on the joggers with their dogs in tow. I've hunted so close to some roadways here in Maryland that I've actually got gased by oil and diesel blowing cars and trucks. Why would I hunt there???? Because it was a main deer travel corridor. I've also had these same deer just get a whif of me or something they didn't like with a wind shift and they start scanning the treetops. The minute they start that they usually just "About Face" and leave. So they can be very tolerant of a lot of stink, traffic and human intervention. Yet, if they get a whiff in the wrong place or from the wrong area they get unglued. I guess what I'm saying is they're very adaptable to the surroundings but still have that knack of winning no matter what. LOL You could probably shoot a deer almost any day off the top of a farm tractor, yet drive a car in the field and they're gone. They're used to seeing and smelling tractors. But take that same tractor smell back in the woods 3/4 of a mile and they aren't used to seeing it there. The safest bet is to go as stinky free and you can be. That includes your 4wheeler smell and last nights party. And... hunt the wind.