Agreed. I don't know why they even made a statement like that years after the game came out.I'm still not buying Crapcom's crap of Nero being Vergil's son! No f'n way! No no!!
Sure, if they had included real hints in the plot of DMC4 that Nero was Vergil's son, then I would have been more accepting. The only hint we do get in Dante handing over Yamato, and maybe the part where Nero activates the devil trigger and says he needs more power like Vergil did.
It's a shame. They could've really done something with Nero and given him a backstory that cemented his family ties to Dante and Vergil. But it seems more like they just suddenly decided years later to explain Nero with a throwaway sentence in a book, a book only released in Japan. That's just plain lazy, Capcom.