whitewidow,
Well, my former boss, Robert Kennedy (RIP), was a friend of Arnie's and watched him and Franco train numerous times back when both were at their best ... and he'd have told you your claims about Columbu's lifting feats are WAY off base from the truth.
But let's be even less specific here, shall we? In Pumping Iron Franco is shown benching 315 at nothing less than 200 pounds bodyweight. He does around 10 reps (still very strong). For him to press 550 would require him to move, minimally, 450-ish for at least eight or so TIGHT and explosive repetitions.
And even less specific ... I, too, have read all his books and none feature pics of him pressing 550. And even if I am mistaken, what would such pictures prove? As if no bodybuilder has ever been photographed with weights far beyond his capabilities. I can tell you from first-hand experience that more often than not a feature on some star bodybuilder will feature training photographs that are less than reality.
Yes, Arnold wasn't as strong as Franco. Everyone knows this.
At around 200 pounds bodyweight, at his most gassed, I'd guesstimate that Franco might have benched around a 500, give or take 25 pounds, but without a pause and with a "thumbs" spot.
It's 30 years later and men who train specifically to build world-class bench presses, and are around 200 pounds, still rarely approach 550 without the use of support gear.
Be sensible.
From any number of angles and probabilities your belief is nonsense.