I fool with face walking, I have 2 different anchors that I use depending on if the course will be mainly short, 40 yds or less or if I will face long ones 80 yds + (rules around here for longbow are generally that you can use any finger position and any anchor as long as index finger touches nock and you can't switch up anchors during the shoot.) Anyway, one thing that I have found with multiple anchors is that the different anchors change my draw length enough that depending on the arrows I have at the time it can adversely affect tuning. With my highest anchor I lose close to an inch. So there is some validity to reddgge's "Forget face walking." unless you really get into it and really figure out what is going to happen to arrow flight as you switch anchors. I tried at one shoot where it was legal for me to do it, and I did ok, but it was a real battle. It even lead to creeping as I began to lose confidence. So for me I can use different anchors but only if I commit to one and shoot that way all day long.