Hiya David, I’ve also suffered from stage fright for 3 decades & more & only recently took up the Wim Hof Method to help me take control of my mind in stressful situations & one of the things they do (totally unrelated to shy bladder) is a breath hold technique & I discovered that I was going to pee myself & only about two days ago I thought, “I’ve found a way to hack my bladder” lol & was interested to see if anyone else had discovered it & im pleased it’s already recognised. I’m still experimenting lol if I hold on the out breath as opposed to the in breath I will get a faster response but it definitely works but yet to use it in proper stressful situations.

It took me about 8 years to tell my first wife and similar for my second wife and 20 years to tell my best friend but I trusted them all. The experience with all 3 was positive.
The common theme with all of them was that they didn't think it was a big deal and understood to varying extents.