Confidence or a good mindset is the fundamental of controlling and even overcoming stutter otherwise your anxieties and fears will be still haunting in your mind and that won't be a good experience, even though you can eradicate stutter through random speech therapies. Confidence is not easy to build up especially if you experienced agonies and torments from stutter, but it doesn't mean confidence is self-deceiving and just puffery. Originally speaking, stutter is not our faults even though perhaps you caught a psychological stutter cause every psychological disorder is not that easy to work out and you have to tangle with your inner evilnesses to persuade yourself there are nothing worthwhile of worries and fears. Cognitive therapies are not hopscotches or hide-and-seeks. For instance Flooding will demand you to reveal your potential disadvantages in speeches and will you have balls to accomplish this mission? Kinda suck right?