in these days rolex chronos had to compete with many other well known chronographs.why risk a bad name in selling plated cases to a continent, where the sweat of the owner will ruin the case quite quickly? the opposite should apply and the price difference would be marginal, because the machinery for the base metal cases in a very small production run would not appeal to a swiss businessman.... the explanation of broken off lugs can be a military one. RAF issued omegaīs had the WW2 alloy cases (with steel backs and bezels) decom. with the lugs cut off. same applied to some lemania chronos for the South African airforce; lugs cut and/or backs squashed. just my 2 cents.... kind regards. achim