For me stuttering is really mental, I've noticed when I'm comfortable and calm with a person and engrossed in conversation I don't stutter (but like you said this is rare). I have tried something similar to what you said here, while talking with people sometimes I don't maintain eye contact but look slightly away from the face, or stand at an angle. This provides me the opportunity to focus on something at a distance and feel like I'm talking to myself instead but this requires a whole lot of concentration and hasn't always worked for me. Sometimes people get uncomfortable since I don't make eye contact as well. They key point is, however briefly I was able to overcome the anxiety associated with saying those blocked words but mainly I just zap back to my senses.