I think that mentality is a very important part and the mindset behind it. I would say that "not caring about people's opinion" is the bigger part, with a mix of the "you can do anything as long as you try" attitude from watching anime :D As for using text - I just kept on speaking at the occasions that I had to. I think I view it as a crutch. Not wanting to use writing probably helped me practice more situations. As I also thought of it as really humiliating - I've had some occasions where people have just asked me to write it down. Now I'm pretty okay, my desire to speak my mind when I see something not being right is bigger than my fear of stuttering.