You should watch Lutter and GSP train together....maybe you would get an appreciation of how high level Lutter's grappling is.....His problem is he doesn't train nor train with guys who push him....which is why he always gasses....
GSP will continue to dominate 170 for now. He's awesome at 170. But Silva is a much different animal. He would beat him on the ground or standing. If GSP takes him down Silva will destoy him in his guard. He's much to long and strong for GSP's ground and pound. Hardy's size negated much of GSP's GNP. It will end badly for GSP and I'm a GSP fan.
I'm not a fan of Silva as a person but can see how talented the guy is.