I've been doing that for a year, and it hasn't helped!
I think that is it. I have been doing the verbal and signal at the same time, assuming she would associate them. But I now suspect that since she had the signal, the verbal was superfluous and she just ignored it. I will work on my timing.If you want to include verbal cues in the repertoire, that's up to you. Just start adding each verbal slightly before the respective signal while practicing, the dog will eventually begin to anticipate the forthcoming signal. Then simply drop the signal.