Seriously bro, his statement is not that far off, although I agree with you he certainly isn't the strongest, but I think he could have been if he trained for powerlifting instead of bodybuilding.
800 lb Deads for 2 reps when the world record at the time was only 925 and with very low bodyfat. Put thirty pounds of water and fat and have him focus on deads for 6 months religiously, he could have easily smashed the 925 world record.
Of course Ronnie could have become a contender at an Elite level, but please don't add well over 100 pounds to the man's deadlift with just some water and fat weight. There is a MASSIVE difference between 800 and 925 pounds.
The deadlift record was well over 925 at that time, too (hell, a 218-pound Ed Coan Sumo pulled 901 almost 20 years ago). And let's not forget Coleman is using wrist wraps when he pulls the double.
Oh, and many top BBs are strongest before a show as they're often on the greatest amount of sauce.