I've was fortunate to bowl with and against Robert in the early 90's. The man has a gift that I believe if resin was never invented, would have 10 more titles. His release just isn't condusive to the modern game. Robert has very strong legs and his forearm is huge, especially compared to his left arm. A good deal of his power is generated from his legs as well as his release.
The messengers I've seen him throw with urethane is scary