Unless you have a propane line going underground in the area you hunt with a small leak that you can smell in the woods than I would have to say it can do nothing but deter the deer. Granted they may or may not associate it with a danger smell, but nonetheless it is a foreign smell that can only be counterprodutive if anything IMO. I'm sure there are a lot of stories about deer coming right around people with heaters in their stands, but how many(or bigger) would there be without?