My experience, they don't respond the same to initial scents, sounds, etc until they have associated it with danger. I used to have a few small urban spots I would go sit and see a bunch of deer. Eventually I realized I didn't need to be in those spots until the end of October when the cruisers started. Anything earlier then that I was just "conditioning" deer. It went from me having no worries I could literally get there slam all of my doors scare everything away and they would come back. In moderation I think you can get away with a lot more hunting urban deer.