I'm in complete agreement with you. Summer or Winter, it's easy to see animal trails if you know what to look for. Every animal has a distinct print, so I'm confused that searchers were confused because other animals are in the area. A domestic horse is not going to join wild horses, so even if there are wild horse prints, at most the prints will cross Ben's horse prints. SAR is trained to do grid searches and spot things that don't belong, but that's not the same as tracking an animal. Perhaps searchers were looking for Ben rather than tracking the horse movements, although that doesn't make any sense since the horse tracks should lead directly to Ben if he was riding the horse.