Rickson could armbar Kong Kong while triangling Godzilla and putting Mothra in a Kimura. The man has eight arms!!!

In all seriousness though, saying Rickson isn't an ATG is absurd. He was the best in the world when the sport was in it's infancy. No one says Jack Johnson wasn't an ATG because he likely couldn't hang with today's HW's.

And as far as running from the Pancrase boys, Shamrock was thier best, and Royce dealt with him. Rickson>Royce. Royce will even tell you that. And unlike most of the Gracies, Rickson could actually crack a little.