Jon,
When possible I always try to concentrate on the crease coming up off the elbow, and low on the crease at that. I do the same thing at a 3-d shoot. It won't score well on a foam target but does a real good job of getting you focused on a live animal.
Of course that is not always the place to look depending on the angle and your choice of stand. I am almost always on the ground, so if I am patient it comes around eventually for me.
Deer usually tense up before the arrow gets there due to the noise, some guys call it ducking the string. Just a lot of muscles contracting in anticipation of getting the heck out of there. That is why I always look low. Worse case scenario the deer doesn't tense up and I may shoot right under it. If it does tense up it is usually a good solid lung hit with a happy tale to follow.
You are a seasoned bowhunter Jon you just need to find that "spot" again.
Good Hunting,
Craig