it is safe to call activate/deactivate but the effect can be reactivated after sleeping.
I guess it is also safe if you add those functions to enable/disable smoke at runtime(you need to recompile the plugin or use the plugin source as a part of your project or just adding those lines will not make them appear in BP).
effects component was never intended to be used for production, we do some improvements from time to time but a generic implementation can not fit everyone’s needs, so no promises.