This thread is intersting. If go caseless then be prepared for it fall. All the people who say they're hyper-viligent, or extra careful forget one thing. Accidents happen, and you can do everything the right way, but still, the phone will fall for reasons out of your control. I get that many people rocking a naked phone has never dropped theirs, and I bet the OP was the same, but yet stuff happens.
Its like driving a care without insurance. Yes you can be the most careful and gifted driver on the planet, but then someone runs a red light, or lighting strikes a tree and limbs falls on you the care. Life happens, and my take on it is, why take changes. If you the naked phone user realizes that and accepts the risk - then more power to you.