One of the things that often tends to work well in live comedy is the ability to elicit laughter from serious, life-changing subjects. Numerous stand-ups have done it over the years and now it’s the turn of Scottish Comedy Award-winner Liam Withnail to use what in his case has been his experience with a chronic illness to make audiences laugh. At the start of 2022, the Edinburgh-based comic believed himself to be healthy. He lived a ‘normal’ life, ate whatever he wanted, and was even training for a marathon. Then he was diagnosed with ulcerative colitis – a type of inflammatory bowel disease –…