I think this implementation will cause problems. This method is not only used for logging purposes, but also for checking resource conflicts. [This line](https://github.com/ros-controls/ros_control/blob/hydro-devel/controller_manager/src/controller_manager.cpp#L251) inside the controller manager populates a `ControlerInfo` instance that ends up being used by [RobotHW::checkForConflict](https://github.com/ros-controls/ros_control/blob/hydro-devel/hardware_interface/include/hardware_interface/robot_hw.h#L73). The dedault implementation does not use the `hardware_interface` field, but robot-specific overloads might (I can already think of valid usecases).

I still think that to support multi-interface controllers, the changes will go deeper than this class. At the very least the [ControllerInfo](https://github.com/ros-controls/ros_control/blob/hydro-devel/hardware_interface/include/hardware_interface/controller_info.h#L43) struct must be modified to allow discriminating which hardware_interfaces are being claimed by each resource, otherwise proper resource confict checks will be impossible.