Oh, Tank's hilarious. He always was. He was great on the mics as a guest commentator back in the early SEG days. And Tank's never minced words. He's not always right, but sometimes he is, and he's right here. Back in the day, Vince McMahon used to actually promote "feats of strength" like this in the WWF...
...and the result was a lot of BS and fake numbers flying around. (Though I love in that vid how he talks shit about the liftoff while holding 700 pounds and even bouncing it up a bit before easily pressing it and pretending to struggle with it with bad WWF acting

) I've heard shit about Hogan and Goldberg benching 700 lbs raw, which is so silly that it'd be funny if it wasn't so insulting to powerlifters and strongmen. Mark Henry was legit and actually accomplished as a powerlifter and his bench PR was 601 in training and 581 in competition. The Rock has always been a freak but his bench wasn't anywhere near 600. There's strong and then there's world record superhuman strength. Very few have the latter. The 500-lb bench club is already super elite. Maybe Ken was in that club, though according to Frank he wasn't. But I wouldn't be too shocked if Ken claimed somewhere between 500-550. But if you listen to gym rats, the number of people who've benched 600+ lbs, squatted 800+ lbs, and deadlifted 900+ lbs is astronomical. It's not unlike the legions of bad ass kumite dudes or Shaolin monks who could "kill" pro MMA fighters with one punch or finger jab. There's plenty of bullshido in weightlifting, too, unfortunately.
For Ken, I'm sure he's mixing facts and fantasy. (Remember, Ken also claims that some dude who trained with Tyson told him that he hits as hard as if not harder than Tyson...maybe Ken believed/believes that, but come on

) That tends to happen with people who (a) did have legit accomplishments but who (b) are older now and no longer have a firm grasp on their history. "Superstar" Billy Graham did an interview about his World's Strongest Man appearance - he finished seventh and hurt himself in the process - and he couldn't even remember what year it was held. I take most of what old athletes claim with a generous helping of salt considering the unreliability of their memories and the unreliability of their egos. Tank's right to emphasize the importance of videotaping himself benching 600 pounds, and he trained consistently and maintained that power to bench 600 consistently over years. You don't just plop down on the bench and start throwing around six or seven plates. It's just not reality.