RE: To pee or not to pee? That is the question.
I remember reading somewhere a study wildlife biologists did on scrape activity and they tried different types of deer urine, human urine and new car scent and that there wasn't much of a different reaction to any of the above. Maybe someone knows of and can post?
From what I've read, do I think they'll notice it, yes, definitiely. Do I think it will scare them or drive them out, no, not at all. I say let it fly from your treestand.
However, if you don't want to leave any scent and are truly concerned about minimal impact in terms of making the deer feel nothing is different, use the bottle. What I've found is effective is to get those small bisquick pancake mix shakers witih the wide mouth. They are nice because they have a handle on them. Make yourself some pancakes and then rinse out the bottles, bringing one along on the hunt and discarding when you get back home.