Ruhl always did super wide grip smith presses. Could have something to do with it.
I think from going super heavy on bench (575+) and genetics, injury... His brother has exact same type of chest. And both these guys were strong as shit. Genetics for massive strength, short limbs, compact and explosive power. Scott Norton said Poppa pump was VERY strong, and if Scott Norton said that you can take it to the bank.
I remember Steiner being asked the most he's ever benched in an Ironman Mag interview, and he claimed 645 in the mid 90's. I know he was in character during the interview and kayfabe blah blah, but he's not the type of guy to lie about something like this. He also proceeded to downplay how good a lift it was by saying something like "so what its not even a world record" ect. Personally I think the guys legit and a straightshooter, maybe a little bitter yes, but he's not a liar.