Mark thought he blew a shot, but after they finally find the deer, he sees exactly what happened.
A great use of modern day tech helped track this deer Mark thought was lost, but good old fashioned legwork turned it up.
When this deer went down, there was no denying the eventual learning opportunity that presented itself.
Though the deer wasn't even 100 yards away, there was a real issue finding out where it was. The power of the quartering away shot was proven by the severed artery, which produced intense bleeding. The broadhead was totally visible during the deer's field processing, and that main artery hit was the thing that saved this shot.
Had the arrow went where he was aiming, it would have flown over the deer's back.