Its very hard.....I don't stare at the rack but I don't care what it is, if you sit there hours and hours and hours pursuing and it waiting for it to show up its pretty intense when it happens and its very hard. Specially with a bow. I don't think its as much looking at the rack as it is the pressure of a rare opportunity being right there and now.
Executing when the time comes is probably the hardest part of bowhunting IMO and what Ive seen the most bowhunters struggle with for sure.