I still don't understand why so many people feel compelled to volunteer the info to the cop, that they're carrying a firearm. When I got pulled over by a state trooper for no front license plate (he wrote me a warning), he ran my TXDL and came back and asked me if I'm currently carrying. I said I was, so he asked if I have my actual CHL plastic on me. I said I did, and asked if he would like me to disarm. He said, "That's not necessary. As long as it stays wherever it is, we won't have any problems." He was a nice guy and wasn't at all annoyed that I did not notify him that I was carrying.
Common courtesy, if you were the law enforcement officer wouldn't you like to know?
An armed, law-abiding shouldn't be a threat to a LEO and communicating that you have a legal weapon on you or in the vehicle shouldn't cause any problems.
I have only had one instance where I was asked for ID since I got my CHL several years ago, I showed the officer my CHL and informed him I was unarmed (I cannot have a firearm where I work). While he may have been a jerk about it (he rudely asked why I was showing him my CHL when I wasn't carrying), I still contend it is better to let a LEO know than to have him ask.
So while there may not be any legal ramifications for not telling the officer (which I believe is thanks to the Motorist Protection Act), I will still contend that it is a good idea and as stated, reduces the stress of the situation by being forthright and cooperative. Most times that can work to your advantage.
Cheers! M2