Blocking...This is the hardest technical skill a catcher has to learn, and there is a HUGE mental component to it. Willingly putting your body (even with protective gear) in front of a fast-moving projectile about to take a possibly unpredictable bounce is a daunting task. Based on what you have said about her reactions in other areas, I would bet that the mental hurdle of blocking in a game situation is going to be a tough one for this player to cross.