Wow. Well, if that works for you, that's great. I'm a middle aged guy in cotton. I've tried shorts with a chamois and haven't found one that works for me. It has nothing to do with the distance; I regularly ride 100+ miles in 'street clothes' with cotton briefs.
As a cotton producer and merchant, I salute you, but your butt is far, far, far tougher than mine if you can ride a centuries in your tighty whiteys.