If Cena ever did make the heel turn would his crowd reaction change that much I wonder? The older fans hate Cena because he's the hulk hogan of our generation and the super duper pg baby face. But considering guys like Orton, Austin etc... have been cheered for years would Cena doing a good heel turn actually pull fans to the new character? Basically all the young fans would now boo Cena with a deep passion but many other older fans would love bringing back the heel persona?
Just some food for thought.