For myself, the courage in question is the courage to be truly honest about what one experiences and perceives. To me, this is the essence of using catalyst efficiently.
Of, course, much of the time this is an easy task, but when it comes to the things we really do not want to know about, this is where persistence and skill comes into play. And often this does require sincere courage.
But then it leads to sincere growth, or expansion of the capacity to experience spirit more directly.