There are simply too many variables that come into play when someone asks if it matters or not.
Things off the top of my head that impact scent and how deer react to it:
- Temperature and relative humidity / dew point
- Wind speed, direction, and flow over uneven landscape (updraft? downdraft?)
- Barometric pressure
- Deer's 'experience' with being hunted/hunting pressure and overall attitude which can change hourly or daily (wisened buck, cautious momma doe, dumb young fawn, distracted rutting buck, etc!!)
- Deer's expectancy of the scent (deer that live near houses/constant bombardment of man-made and human smells vs. deeper woods deer, etc)
There are probably a billion others that I'm not thinking of! If these factors were constant, then yes we could determine what works, what doesn't, and so forth. But they're not. There are too many variables to know if you see more deer any given day because you smell less, or because you smell like apples, or because the deer are simply moving that day.
It's not wrong to think about scent, especially scent reduction, but I, too, wonder if some folks put too much thought into it. At the end of the day, if a deer is going to smell me then it is going to smell me no matter what. A deer is going to care if it's going to care, no matter what. I just try to enjoy my time hunting and don't stress over my scent to the point where it becomes labor instead of enjoyment.
If someone gets a kick out of extreme scent control, then power to them!