dc_yeager, I'm in accord with MechAg94: It is absolutely zero hassle to have both the driver's license and the handgun-carry license together in one's billfold. Stopped and asked for ID? They come out together. I fail to understand why that's a problem.
It is of course a case-by-case sort of thing. In Washington there is no duty to inform. Informing when it isnt necessary can complicate matters. You now have a more nervous officer on your hands, and now you get to surrender your weapon and step out of the vehicle, when you were previously looking at signing a piece of paper and going about your way. I'm sure that police opinions differ as much as everyone else's however, I have been told by several officers that they would prefer not to be informed, as it complicates the issue for them as well.