Plugs, sockets, FCUs etc are meant to handle that ok. But in reality they don't always. Like you I'd expect a hager to be ok.
Years ago we had an FCU that fed an immersion that had split open. With no RCD it took time to realise. The thing was overloading & cycling on & off due to overheating its stat. The FCU was ok with it thankfully, though discovered to be rather hot.
NT