Chet,
While I won't go so far as to say a pistol without a round chambered is useless, I would say that it defeats the point.
While in many cases just having a pistol is going to stop the situation, if it becomes needed, there are the times where you would have to fire. In those situations, you will need that firearm to work, and to work quickly. You will not want to take an extra second to have to chamber a round, and that extra second may mean the difference between life and death.
Remember, you can only draw your firearm in Oregon if it becomes a life or death situation, your attacker has the Means, the Motive, and the Opportunity to kill or maim you. Drawing your firearm is considered lethal force, whether or not the chamber is loaded.
If you reach that point, I doubt that you want the only thing between you and death to be an unloaded firearm.
I know that someone earlier in the thread commented on liability in case of an ND/AD, but really, you can take precautions to keep that from happening. If you have a quality handgun, and you have it mounted in a quality holster, something fitted to your pistol that covers the trigger, your pistol will not fire while it is holstered. PERIOD.
You will get used to chambering a round prior to holstering, although it feels odd at first. Just use the same rules that apply when you are at the range. Finger off trigger, gun pointed in safe direction, but then just put it in a good holster. When you need to handle the actual firearm, just unload it before you do anything with it.
I think if you are planning on carrying with a the chamber empty you need to rethink why you are carrying a weapon in the first place. If it is for defense, than you really should carry with a chambered round.
I.G.B.