I read it at least once somewhere and there are some articles in the internet about it. I have to admit though, that the credibility is questionable. Nevertheless, there is an old article (The Sweet Science: Why we never saw Foreman-Tyson). Cus D'Amato and Tyson watched the first fight between Frazier and Foreman. D'Amato said to Tyson, that Foremans style is deadly for short swarmers (just tall fighters with good movement could beat him)...Tyson was fearful of Foreman (you can google it).