Just to clear up, I likened Snape to Riddle as both turned to the Dark Arts because of the power it held. However, Harry, as much as he has suffered trauma and been bullied has never done so. That was my main point, that I understand what DD meant when he explained why Harry was so special.

I also wonder how much of Voldemort's megalomania and insanity is hereditry. Years of Gaunt inbreeding exhibited as insanity in the previous generation, it would not be impossible for Voldemort to have gained a few flawed genes.