Why a captured French predreadnought would be hard to absorb

Could the Royal Navy efficiently put a captured French predreadnought into service?

The joke is that British engineers would replace almost everything, perhaps retaining only the nameplate.

A hypothetical Royal Navy engineer responds to a captured French predreadnought by proposing replacement boilers, engines and guns. The joke escalates until even the hull is doubtful and only the nameplate is certain to remain. It extends the criticism of French machinery arrangements into an imagined refit, without an actual conversion proposal or cost estimate.