As someone who chipped his iPhone 4′s screen by dropping it a full 8″ onto a wooden step, my answer is “Oh hell no.” My iPhone will always reside inside case.
Caolo’s comment was in response to a Gizmodo piece encouraging people to go case free. I have always been a case guy. Not for resale value, but because the case is more easily replaceable than the phone. I take pretty good care of my phone, but have still dropped it, or put it somewhere where it can get scratched. If any of this damage is ever enough to bother me, I can just take the case off and get a new one. If I didn’t have a case, I would be stuck.