A former Arizona SWAT commander has poured cold water on a “highly improbable” theory that Nancy Guthrie was abducted via rugged terrain at the back of her home, insisting whoever was responsible for her disappearance “clearly had to go out the front.” Authorities have repeatedly scoured the remote terrain behind Savannah Guthrie’s 84-year-old mom’s Tucson home since Nancy was first reported missing on Feb. 1 — fueling initial speculation that her kidnapper could have used a remote track to