I know from personally experience that sometimes wearing the least amount is the most comfy while exercising, and I know from experience that compression shorts are very comfortable to run in, and don't give wedgies or anything, and split running shorts look goofy, but when it's humid and hot, they are a god send. A friend who is a sponsored marathon and ultra runner wears the bumhugger shorts in marathons and training, and says they are THE most comfortable things to run in. Bodyglide only helps so much with chafing.
Also: if you go out and do a 15-mile run on a hot, humid day, you need electrolytes, but Gatorade would make me puke. REAL Gatorade wasn't a sugary drink. I drink water and will eat some salty food while running, and that's fine for me. HEED or something won;t make you sick like Gatorade, and HEED also tastes icky, like original Gatorade did.
Oh: I read Misty and Kerri have total say in what they wear and train with. I have specific running clothes I like to wear for specific things, and get all twitchy when I can't wear what want.