Definately true with the high vis vest
All it really takes is looking the part, and acting like your supposed to be there. People don't really question the look of things much nowadays, that's why it's so easy.
I wear a high vis vest while riding, and people think I'm a cop or some kind of authority figure, because they stay away from me in traffic, never ride my ass, wait instead of pulling out in front of me, actually look out for me, and a host of other courteous things I've never gotten even once while riding without it. It works so good here, that I never ride without it now.