The different overweight values weren't a range (between 500 and 5000 kg). These numbers were given by using different approved calculation methods (male, female, infants with specific values or all at 76 kg each). Since the 500 kg results from an "approved" calculation method, it basically represent the "legal overweight" with no need to consider higher value in regard to "book operations".
There was a "high legal overweight" of 500kg, no runway inspection and a missing spacer which all played a role in the tire destruction. Which of the elements leading to fuel tank damages and fuel ignition following this tire destruction could have been 100% avoided by BA and not AF?
Considering the runway FOD and since BA wasn't conducting much runway inspections, it wouldn't have been avoided by a BA concorde. Again, what in such case would have led a BA aircraft to an 100% safe outcome?
I know that AF is definitely responsible for the violations that led to the tire destruction (the missing spacer above all) and that the BEA obviously failed to highlight it. I still want to look beyond that and I'm not convinced that such tragedy could have been avoided in all cases by a BA concorde bursting a tire.
It's my personal opinion to believe that there was a basic weakness within the aircraft's design which had little to do with the airline. Blaming AF's poor operational qualities doesn't demonstrate the aircraft wasn't presenting an unacceptable risk level.