After re reading your thread, realized that I got side tracked and didn't really answer your question.
It's been my experience that most deer during bow season don't jump the string, but I won't shoot at a deer that's on full alert either. Tomorrow is another day. Once gun season opens, and the deer have been shot at and chased around, It's a whole nother ball game.
To answer your other question, I've always liked to pick a spot just a little lower than the middle of a deers chest. I've shot over and under some deer over the years, but a shot there gives me a little leeway both ways. JMHO
Bob