Well, a power that has a requirement like "the ally must be able to hear & understand you" might be literally a command, as a name like "Commander" might imply, or it might be a warning, pointing out an opportunity, offering advice, giving encouragement, or coordinating a pre-arranged or oft-used battle plan/trick/maneuver. Without such a restriction, a maneuver that granted an ally an attack or bonus might also/instead involve creating an opening by binding then enemy's weapon or shield and/or distracting it.