I haven't read the article (it's a little late in the day for academic prose) but have done a lot of scent work with my dog as a hobby, and talked with a traine

I haven't read the article (it's a little late in the day for academic prose) but have done a lot of scent work with my dog as a hobby, and talked with a trainer who does it for a living (bombs, drugs, etc). Handler bearing absolutely plays a role if you aren't careful. One way our trainer taught us to fix this was to try to pull the dog away from the scent during training. If he follows us, we leave the room and stop the activity. The idea is to tell him that humans are stupid, they don't know where the scents are, so stop trusting them, because then your game and reward goes away. It worked very quickly and now he locks his legs and won't move when he's got the odour. This avoids accidentally pulling him off the odour when you're covering a large area at a brisk pace. Regardless, whenever possible one of us hides the odour and the other runs the dog. This helps us avoid any preconceptions (such as focusing on one corner of the room, missing potentional scent cones from cross-drafts). Humans can still mislead the dog like this so it's best to form good habits and have an open mind.