This is all nice, but the best way to be safe carrying during a stop is to be courteous when the officer initiates contact. You don’t have to agree with him, but let him know you are not a threat and he can conduct his business without calling for additional officers. Usually yelling, “What the F*ck did you stop me for,” before he reaches your car will cause him to become concerned. Yelling, cursing, demanding you know your rights, and informing him he can’t tell you what to do, is another good way to make a cop raise his guard. As noted in most of the posts so far on this topic, Freepers that were at least business-like courteous, found the officer to be the same.
Chris Rock was all over this.