I found out first hand that if you don't bend at the waist it pulls your line of sight out of sinc. I had a buck come if fast and didn't use my head, just positioned my self for the shot and didn't bend at the waist. It was only a 10 yard shot but at that angle you need to bend even more and I didn't. It made my shot go to the right of my aiming point but I luckily still got my buck, my biggest to date. I went and shot my bow from an elevated position after to see what happend and tried a few different things and found my shot to be off if I only dropped my arms. It pulls your eyes down, almost like looking at your nose thus pulling the line of sight out of wack.

Needless to say, I practice from an elevated stand all the time now!!!