'She does her business of delineating the surface of the lives of genteel...

[myaimistrue]

...English people curiously well'?? What does this quote mean?

[Scaramanga]

It means your no fun at parties

it means she "outlines posh english people's lives". Or basically summarizes what the lives of posh english people are like, which is to say they are an obfuscation of the clarity of intelligent conversation at an unnaceptable level of incoherent and babbling self importance.

hope that helped.

Incidently I'm from Ireland and when I meet someone who needlessly complicates the beauty of the english language to sound important or to curry literary favour generally i tend to place them in the over simplified yet refreshingly clear category of the c*nt.

[old lady]

It means that she describes what genteel English people do - but stays at the surface level. She doesn't delve into their true thoughts and motivations, but just outlines the superficial bits.
It's what's known in the trade as damning with faint praise, because if you think about it, if the writer doesn't bother to go below the surface, then it misses a tremendous amount of potential