When healing another unit/player as medic, the success of the heal action is highly dependent of the relative position of both units. A slight movement of either of the involved may result in no healing being applied without additional feedback to the player, that thje action has failed.
As the logical center of a unit is rotated together with the unit, even looking in another direction while healing/being healed may result in a failure of the action.
Expected behaviour: Healing should be always successful when both participants stay below the distance in which the healing action is displayed in the action menu.