I'm gonna say there is more to the equation than just tree in front, or tree in back. To compare, go to where the deer normally walk. Drop down to there height and look at where your sitting. Would you be less visible or more visible on front of the tree. What's behind you? Lots of brush? Open timber? Skyline on a hill?
You just need to not look like a human sitting there and not be seen moving. The more you do that while being down wind, the greater your chances are of killing a deer that comes close.
Oh yeah, there's definitely more to it than just tree in front and tree in back. The walls are about 3 foot tall, all sticks and branches from the area, annd that can hide a lot of motion. My uncle actually found this thing 30 years ago while scouting some state land. He shot a good 8 pointer his first sit there that day and we've been hunting there successfully ever since!
It is open timber, there's some super thick cover about 80 yards in front of where we sit that they use for cover a lot, and the deer tend to move from that cover passed the blind to open timber behind the blind. Sometimes they travel in front of the blind too, which is where that tree in front really helps hide your motion.
I had a good buck come in from my right once and he was moving through some of that thick stuff from right to left. As soon as that tree in front of me was in between us, I was able to stand and draw without him noticing at all. I had a small window to shoot thru and he stopped right in front of it. Then some does came in from the left and he ran thru that window chasing them, and I never got a shot.