I suspect that diphallia is more common than yea olde Wikipedia claims. There was a white trash Texan, (Mr. Mitch), who appeared in a series of heterosexual porn about a guy with two dicks, and his penises were certainly authentic. No prosthetic penises could have endured the workouts he suffered through all in the name of porn. Plus, he was marketed as an "escort" by the porn company as well as a favorite attraction at the Adult Porn and Video Convention in Las Vegas. His penises were stacked one on top of the other with the bottom one being slightly (but not by much) shorter that the top penis and he had the good fortune to cum two separate times. Once he shot one dick it would go limp as the other continued to stay hard and ready to blast from what must have been a complete, secondary sexual/urinary system. It normally cost $25 to fondle him and check out his goods at the Vegas convention.
However, when he opened his mouth to speak, any interest you might have had in him was immediately doused by how clueless and dull he was.