True, however, most coyotes are hunted in low human density areas and in most of those areas the coyotes get shot at with shotguns, bows, rifles, from vehicles along roads, from little 'ol ladys front porches!![8D]SO inthose areas, if a coyote even thinks it smells human, it will USUALLY, (there are exceptions to every rule in coyote calling)turn tail and run.
Example of an exception! Two weeks ago I was filming over the shoulder of a single shooter that had his A.R. I called in a single coyote that he shot at about 40 yards, I kept calling and a second coyote came in. On his 12th shot, he killed the 2nd coyote. How many coyotes have you ever seen that did trun tail to run after the first or second shot? Not many!!
I've had coyotes plenty close that I swore should've/could've smelled me, but didn't react as I would've expected.
Like ya said, not all areas are the same! We all have to learn our core calling area and adapt to our calling conditions/situations!