So the actual in game feature is NOT factual as far as I know. The previous thread alluded to this in the footer of the post. However, the question about what people think about this still remains..
Maybe the volume of your voice will determine how powerful the shout is in game.
Would you be interested in using your own voice to issue powerful shouts in the game? Does the possibility of having to learn and remember phrases in real time intrigue you? Or will this introduce unecessary complications or take away for the flow of combat?