Inherent Weakness ?

[ireload2]

I have reloading data from IMR for the .308 where 4 of the loads are shown to be 59,000 PSI (transducer). You have to remember those loads will have some statistical variation and some individual rounds will have higher pressure than the 59,000 PSI. (transducer).
But for Europeans with rifles that would be chambered and proofed to .308 the proof pressures are much higher. So much higher that I am not sure a #4 would pass or even survive.
US proof requirements for the .308 are 83,000 PSI to 89,000 PSI (by transducer)

And yes Winchester IS the final design authority for the .308 Win cartridge.
SAAMI is the standardizing body but Winchester OWNS the design.