I took Ruger back to my girlfriend's place tonight, and when I got there I put the collar on him. Not one peep out of the little guy, and he was quiet and affectionate all evening. Earlier that day I took him for two walks, where he barked quite a bit, and we took both dogs out for a walk and he also barked a lot then. Miles, my girlfriend's dog, also barked a lot at the TV and Ruger usually joins in. Not this time.
So far so good, and he may have already put two and two together with the collar and not barking. He didn't seem happy when I put the collar in my pocket when we left for my girlfriends.
The instructions said only to use the collar when you don't want him to bark, and that's what I'm doing. He's a good little watchdog and I don't want to kill that.