Public speaking can be terrifying. For David Nihill, the idea of standing in front of an audience was scarier than cliff jumping into a thorny pit of spiders and mothers-in-law. Without a parachute or advanced weaponry. Something had to change.

In what doesn't sound like the best plan ever, David decided to overcome his fears by pretending to be an accomplished comedian called "Irish Dave" for one full year, crashing as many comedy clubs, festivals, and shows as possible. One part of the plan was at least logical: he was already Irish and already called Dave.

In one year, David went...