IMO, even if a word/phrase is constantly repeated, in the end the bird will only say what they want to say (just ask Camille

), if they even want to say anything at all. Jerry is my biggest talker and I honestly think that:
1) talking to him ALL the time and
2) speaking in an animated and excited voice have been the main motivators for him to talk.
He ONLY says things that I say (he then makes up his own word combinations though) and I speak in an animated voice with him - meaning we we make goofy sounds to each other and I put inflections and emphasis on certain words or phrases and when he mimics me he puts in those same inflections - it's really cool actually. My husband talks to him too, but not in an animated way, and he says NOTHING that hubby says (and thank goodness because sometimes hubby tries to get him to say bad words...

).