Question to you: How do you understand the psychological dynamic of your chronic shyness? Is it a fundamental lack of self-confidence? It could well be that you haven't INTEGRATED your much younger self (whose shyness was intimately tied to feelings of insecurity and a lack of self-confidence) with your adult self, who has learned through experience that he's highly skilled and can certainly trust himself to perform well in front of an audience. If this is possibly true for you, I'd suggest you see a well-trained EMDR therapist to deal with past trauma that's led you to be overly sensitized to present-day situations that, otherwise, you could handle with very little (or no!) anxiety at all.