Who knows for sure, right? I do know this, some of the greatest hunters of all time (native americans) used to stand in their camp fire smoke as a way to mask the human odor, long before scent killers and such arrived.
Deer typically will not spook just because they smell smoke or other foreign odors, unless they associate that smell to humans, as they smell smoke from burning fields and such all the time. What they do not like is humans. So if they smell you, your busted.
Just read an article last night that five different deer biologist from all over the country agreed that deer cannot distinguise human urine from fox, coyote, or coon urine. Therefore, you can pee in your stand, on your stand or anywhere near your stand and not spook deer.
Hummmm.....not sure I am ready to believe that or not. If I decide to experiment, it will definetely be towards the end of the season and after I' ve filled all my tags! Certainly would be easier to just let er' fly from the platform wouldn' t it?
Keep on keeping on........