It was a smartarse reply but on a serious topic.

http://www.time-to-run.com/tips/chafing.htm

Once chafing starts, you go from tender to unbearable in about 10 minutes as each subsequent layer of skin worn off is softer and more tender.

I have had bleeding nipples form running, and also been so badly chafed from running in regular shorts that I walked like an old-style gun-slinger for days afterwards. The jolting from riding on NZ's less than smooth roads in loose cycle shirts is also not a good scene without a tight polyprop singlet or shirt as a base layer, and/or a good smear of anti-chafing cream.

I wish I had half your luck if you've never experienced chafing.

Cheers