The idea of a possibly armed situation is to immobilize the suspect, get him cuffed and then searched ASAP.. The only exception I can think of is a felony stop involving a vehicle and other suspects. You do then want the suspect to walk backwards (away from the vehicle) towards you until they can be cuffed. The officer had all day to enact this stop. The hallway was clear. No other suspects known at the time. He had all day to order the suspect to do what he wanted. In my opinion.. a bad shoot.
Arizona is an open carry state...every situation is a ‘possibly armed’ one.