Local colloquialisms differ... Sorry for the misunderstanding if "raised" doesn't mean the same thing everywhere and I took it differently than you meant it... and then don't feel some guy with no experience or answers adds value to the discussion.
But you do you and I'll still be suspicious of the claims. I've raised enough 205 day 600 pound calves to know how hard it can be for most people, even with good cattle, and I've seen enough not get past the 500 mark with better genetics than Corriente. If you automatically go to insults and don't want to be civil then that makes your information suspect too.
I don't believe anyone can raise a 205 day 500 pound calf on a 600 pound mother cow reliably.