Anyone who's tried sneaking up on mulies will tell you it's a very tricky game. They have the eyes of an antelope and the nose of a whitetail, and they'll bust you in a heartbeat.
This is especially true when you have to resort to a belly crawl to get in close as Melissa Bachman does here. She has spotted the bucks on a fenceline, and her only hope is to attempt to crawl into bow range. This is the classic 'Kayser crawl' that she learned from hunting with Mark Kayser.
Sometimes it works, sometimes it doesn't, but ALWAYS it's an exercise in finding every single sticker, twig or stone that lives on the terrain. Oh yeah, and you need to be pretty silent, so no yelping is allowed no matter how painful the crawl.
Kinda makes you long for a comfortable sit in a groundblind, but hey, it's all part of the hunting experience.