expChick,

Chamois butter helps prevent chafing by reducing friction. Chamois is not just to keep you dry. For one thing, I don't think there is any short or any fabric out there that will truly keep you dry, unless you never sweat. And how many of us can say that? Yes, some shorts are better at wicking than others but if you ride hard, you will sweat and you will be have a damp chamois. The best thing thing you can do is get out of the shorts as soon as possible after riding and clean off. I can't speak for the problem of yeast infections, rarely suffer from it but I'm sure you'll hear from someone with experience.