It’s funny because I am so back and forth on this. I love to use my blue tick as my test subject, but like you said he’s trained to follow scent. I’ve seen him follow disturbed soil trails that were a day old like it just happened. I remember training him as a puppy. We used raccoons to teach him to blood trail because well we have a ton of them around and no real restrictions for hunting them. So we have accessible fresh blood and scent to use. Anyway the first couple times he didn’t really know what a raccoon was. I’d lock him up. Shoot a coon. Use the blood and body, I’d drag it for a yard then lift it and walk a couple yards the drag it again basically repeating process for 30 to 40 yards. After a couple hours, I’d let him out, I’d use the coon tail with a little blood on it, have him sit and sniff it, then give him a treat. I always would say where’s my bag? Let him run and sniff out the coon. When he located it, I’d give him a treat again or a piece of hide to chew. He loved it. Well we do some refresher smelling every summer to get him ready for the fall, last season I got real tricky and barely let the coon skin touch the ground (maybe once every 5 or so yards. I created a long (around 140 yards give or take) looping trail and circled back some (about 20 yards) and nailed the coon about 7’ high in a tree. After 2 and a half hours, I let him out, he sniffed the tail, I said where’s my bag? He began sniffing the ground per usual, he got about 30 yards and the wind picked up. My dog took his nose off the ground stuck it straight in the air and made a dart directly to the tree where the coon was nailed up. He didn’t follow the looping trail, he didn’t get even slightly confused. He made a bee line to that tree and started jumping up trying to fetch that skin. (So much for me being smart) I always wear rubber hip waders and long sleeves when I do this so that he isn’t following my smell only the blood and fur.
Now a deer has more glands in their nose than a hog, a dog, bested only by a few animals (elephant being number one lol) does that actually mean they sniff better? Scientist seem to think so. I said all of this because I feel like their noses are amazing. It’s our intelligence that sets us apart from the animal kingdom. So I know a trained animal can do amazing things with their noses. I also know deer aren’t trained, however they eventually learn to assign danger to specific smells and sounds. So to me, your scent control can be as impacted by the area you hunt as it can anything else. If you hunt an area that is highly visited with human traffic all year long and no one is shooting them until November, they probably don’t associate human smell with danger. It’s why hunting in highly populated urban areas isn’t as challenging in my mind. Deer learn to associate the sounds and smells of humans and they have no reason to fear that sound or smell until you shoot them. If you hunt in flat land, cold areas, thermals can be more problematic in my mind than hill sides where there’s more room for wind to carry. Or even change directions (up draft). I could be wrong but that’s how I see it. Down south it’s hot! Like really hot and the temps from sun rise to 10 am might fluctuate 20 degrees or more in that time. But evenings might not change 8 degrees so I might be in the minority but I don’t worry about thermals as much once I’m in the tree. However no amount of scent lok or control in the world helps control odor when it’s 88 to 95 degrees during bow season (our rut) and you are literally pouring sweat. So for that reason I think the wind is my only friend. If lived in a high pressure area where people are only entering during hunting seasons (such as Sante Fe swamp WMA) , the wind is even more important to me. If I’m like say in Ocala where there’s hunting pressure but year around people are in the woods hiking trails, riding the off road jeep courses, biking ect even though the hunting areas are different, the deer still have interactions with people. They hear them, smell them, see them and never get shot at. So in that place, maybe scent control could be enough to trick that deer into believing it was older and no danger was present. I often ponder how well smell carries in the extreme cold like MI and WI.Hospitals keep it cold because it slows the spread of germs. Part of that is cold air is dense, it sinks to the bottom where draft is less of a concern. Basically it helps keep air spread particles from reaching our respiratory tracks.(notice I said helps not eliminates) I often wonder if you’re in a wooded area with light winds or blocked winds, and real cold weather, if that would help keep the scent right under the tree you hunt. How would thermals work in that situation where your body temperature puts off heat that’s way above the surrounding air temperature? Would that heat some of the air pockets and float? Or would the cold air just force it down to the base of the tree where there would be even less wind to disturb it? I’m not a scientist so I don’t know how that would work. I have theories. And honestly my theories could be way wrong. So I think in certain situations or areas, you might be able to fool a deers nose just like we use calls to fool their ears, or camo and being still to fool their eyes. However there are some situations that I don’t think anything will ever stop your scent from being detected and I don’t care how much Scentlok,scent free detergent, scent free deodorant or whatever else you use. So yea I am torn and since every situation is different, there is no right or wrong answer in my eyes