Queen Elizabeth machinery and design-risk management

British constructors did not reject new small-tube boilers simply because they disliked innovation. The Queen Elizabeth class already combined higher speed with several other major changes, so its design team chose not to add another unproven variable. The decision is presented as deliberate risk management: take large advances in selected areas and defer a further leap to the next generation. On this interpretation, the caution still sacrificed performance because the ships might have reached about 28 knots with the newer machinery. The example separates prudent risk reduction from the broader postwar habit of preserving a process merely because it still worked.