I heard the guy who's pushing these theories about the earth being smaller, in the past, and growing on Coast To Coast AM a while back. It didn't really pass my personal smell-test, but was interesting enough to file away with a big "?" on it. He actually posits that the increasing gravity is and size is coming from mass appearing through a multidimensional conduit in the center of the earth. I suspect he has found some interesting nuggets of truth amonst all the other stuff he's talking about.
I'm pretty sure from what I've read that a dinosaur would not survive one standard gravity, and there has to be some explanation for this, because they do, in fact, appear to have lived.
Not enough time for any sort of an expanding Earth theory to account for large dinosaurs. They also find ancient stone structures which neither ancient nor modern technologies could account for (200-ton fitted stones etc.). Those also require reduced gravity, and were not created by dinosaurs and are not 70,000,000 years old.