Grandfather Paradox

According to Steven Gibbs, the Grandfather Paradox cannot exist because when you go back in time you travel to a parallel earth on an alternate timeline close to ours. You would kill a man that was close to your grandfather, but not the same.

Who knows if that man would even marry your grandmother. He might remain single or die in a war.

In fact, Steven Gibbs claims the HDR is designed so you cannot go back to the direct past. So to prevent gambling and such. This eliminates the possibility of a grandfather paradox.