Never, ever wear pants when cycling for any reasonable time, you're just asking for trouble."
What a load of rubbish. Whenever I ride it's either boxers under baggies or my 661 armoured lycra shorts under baggies, I've done XC racing in boxers, long distange rides, multi-day rides, a 24km tour de france road climb… Just because it doesn't work for you don't assume it doesn't work for anyone.
On Friday at the top of a climb I was greeted with the sight of an older gentleman riding in just his pants, his shorts and t-shirt draped over the handlebars.
I did an offroad triathlon race in a team once, and was confronted with the site of a guy on a mountainbike in speedos, nothing else. Nearly fell off I did.